What do codes such as K100, K210, K310 and K335 mean on the 2027 Singapore-Cambridge Secondary Education Certificate (SEC)? They identify particular national examination subjects and syllabuses. The code helps families distinguish the subject, its G-level and, where relevant, its combination. The student’s original Posting Group is not an examination code, and a familiar subject title alone may not be precise enough to select the correct revision materials.
Here is an easy starting example: the 2027 school-candidate lists identify English Language as K100 at G1, K200 at G2 and K300 at G3. Mathematics is K110 at G1, K210 at G2 and K310 at G3. Three syllabuses may share the everyday name ‘Mathematics’, yet their examinable content, assessment arrangements and required thinking need not be the same. Always open the syllabus matching the child’s registered subject level.
This is a practical guide for parents, students and teachers who have seen old O-Level or N-Level numbers on past-year papers, found different codes in an online search, or wondered why standalone Geography and Humanities (Social Studies, Geography) are separate 2027 subjects. No examination label measures a child’s potential. It simply helps you find the right official document and prepare accurately.
Independent eduKateSG parent reference checked 18 October 2026 against SEAB’s 2027 G1, G2 and G3 school-candidate catalogues, which identify the 2027 code alongside the 2026-and-earlier reference code. This is a navigation guide, not an enrolment or eligibility decision. SEAB and the student’s school remain the authorities for their own examination and registration procedures.
The fast answer: recognise your child’s 2027 SEC codes
| Subject example | G1 2027 | G2 2027 | G3 2027 |
|---|---|---|---|
| English Language | K100 | K200 | K300 |
| Mathematics | K110 | K210 | K310 |
| Chinese / Chinese Language | K120 | K220 | K320 |
| Computing | K127 | K237 | K349 |
| Art | K126 | K236 | K347 |
| Nutrition and Food Science | K125 | K235 | K346 |
| Design and Technology | K124 | K234 | K345 |
These are examples of names and codes appearing in the official 2027 school-candidate lists, not a promise that every secondary school offers every subject at all three levels. Always verify your school’s actual teaching arrangements and the student’s individual eligibility. If a subject has a special status, a higher-level variant or an approved-school restriction, consult the relevant SEAB notes.
1. What a subject code does—and does not—tell you
An examination subject code serves as a precise identifier. It helps the school and examining authority refer to the correct syllabus, examination components, documentation and subject registration. For parents, its main value is avoiding an accidental mismatch: opening a G3 syllabus for a child currently preparing a G2 examination, or buying an old-paper collection for a different Humanities combination.
A code is not a ranking of the learner. It is not a score, a grade boundary, an IQ measure, a guaranteed post-secondary route or a promise that an elective is offered in a particular school. The student’s qualifications are determined by examinations actually taken and officially reported, while future pathway eligibility is determined by the relevant admissions rules.
The letters and numbers are much less important than what they point to. A parent who understands how to retrieve the correct syllabus can check content, paper formats, assessment objectives and, where relevant, coursework, practical or oral components. That is more useful than memorising a long catalogue of numbers.
2. What changed from O-Level and N-Level codes in 2027?
From 2027, the national N(T)-, N(A)- and O-Level examinations are brought together under the SEC framework. Students take national subjects at their respective G1, G2 or G3 subject levels and receive a certificate showing the subjects and levels they sat. SEAB states that the overall examination standards remain unchanged under this change in qualification name and arrangement.
SEAB’s 2027 directories display two code columns: the 2027 SEC subject code and a 2026-and-earlier reference code. This makes it easier to recognise a familiar subject from older papers without treating an older code as the current 2027 registration code.
| 2027 SEC example | 2027 code | 2026 and earlier code shown by SEAB |
|---|---|---|
| G1 English Language | K100 | 1195 |
| G2 English Language | K200 | 1190 |
| G3 English Language | K300 | 1184 |
| G1 Mathematics | K110 | 4046 |
| G2 Mathematics | K210 | 4045 |
| G3 Mathematics | K310 | 4052 |
| G2 Additional Mathematics | K232 | 4051 |
| G3 Additional Mathematics | K341 | 4049 |
A student revising with a 2026 O-Level English paper labelled 1184 may be looking at material related to the G3 subject now identified as K300. That historical relationship does not mean every question, topic or assessment arrangement is automatically unchanged. Review the actual 2027 K300 syllabus to see whether there are revisions, updated formats or explicit paper instructions.
The same care applies to Mathematics and Science. Treat a historical code as a cross-reference, not as proof that the latest syllabus is identical. A past-year question is useful only after checking that the underlying topic and task remain relevant.
3. How Posting Groups relate to the code
Posting Groups—PG1, PG2 and PG3—are used in the transition from PSLE to Secondary 1. They are not permanent single-subject examination packages. Full Subject-Based Banding allows individual students to take subjects at different G-levels according to the applicable school arrangements and their learning needs.
A PG2 learner might be studying G3 Mathematics while taking another subject at G2, for example, if the school has arranged those levels. In that situation, the correct Mathematics syllabus is the G3 one; the parent’s revision search should be tied to the actual subject level, not ‘PG2 Mathematics’ as a blanket assumption.
A useful household habit is to keep a simple table of subject, subject level, exact syllabus code, teacher and next assessment. This avoids buying or practising the wrong materials while protecting the child’s identity from being reduced to a single original posting label.
4. Mathematics: same family name, distinct subjects and demands
For the 2027 school-candidate SEC, G1 Mathematics is K110, G2 Mathematics is K210, and G3 Mathematics is K310. These are straightforward examples because the everyday name remains recognisable. But the structure of reasoning a student must demonstrate should be checked in the actual level’s syllabus rather than assumed to be universal.
A learner who correctly finds an unknown value in a basic linear equation has shown a useful foundation. At another G-level, a problem may require more complex algebraic manipulation, mathematical modelling, graphical interpretation or multi-step justification. Good teaching starts with what is secure, extends it and then tests whether the learner can use it in a new situation.
Additional Mathematics has different codes and is not merely Mathematics Paper 3. The 2027 G2 directory lists Additional Mathematics K232, while the G3 directory lists Additional Mathematics K341. Parents should distinguish the actual subject from a general ‘hard Maths’ workbook and confirm the student’s registered subject.
For paper-specific timing and question selection, use the PG1/PG2/PG3 SEC Mathematics paper management guide. Code identification comes first; timed practice then has to match the correct subject.
5. Science: why you cannot select a syllabus from the word ‘Science’ alone
Science offers a particularly useful lesson in precision. The G1 directory lists Science K123. At G2, the combined subjects are separately listed: Science (Physics, Chemistry) K223; Science (Physics, Biology) K224; and Science (Chemistry, Biology) K225. At G3, combined-science pairs are likewise separate from single-discipline Physics, Chemistry and Biology subjects.
| 2027 examined Science subject | Code | Why the distinction matters |
|---|---|---|
| G1 Science | K123 | Use the specified G1 Science syllabus, not a different level’s Biology or Physics syllabus |
| G2 Science (Physics, Chemistry) | K223 | The registered pair determines the science disciplines |
| G2 Science (Physics, Biology) | K224 | Biology is part of this pair, not Chemistry |
| G2 Science (Chemistry, Biology) | K225 | Physics is not the paired discipline |
| G3 Science (Physics, Chemistry) | K326 | Use this G3 combined-science syllabus |
| G3 Science (Physics, Biology) | K327 | This is a different G3 combination |
| G3 Science (Chemistry, Biology) | K328 | The components differ from Physics-containing pairs |
| G3 Physics / Chemistry / Biology | K323 / K324 / K325 | Each discipline has its own separately listed national subject |
A parent buying a thick ‘SEC Science’ book without checking the combination risks paying for content that the child will not be assessed on while leaving gaps in the subject they actually take. A more efficient approach is to identify the code, read the prescribed content and practise the needed scientific skills.
The educational goal does not change: students should be able to observe, explain, reason from evidence and apply ideas. Accurate materials make those goals easier to achieve.
6. Humanities: standalone Geography is not Humanities (Social Studies, Geography)
A common source of confusion is seeing ‘Geography’ or ‘History’ in more than one 2027 examination title. The subject title and code must be read together. At G2, the catalogue lists standalone Geography K226 and Humanities (Social Studies, Geography) K229. At G3, standalone Geography is K329, while Humanities (Social Studies, Geography) is K335.
| What the parent sees | 2027 G2 | 2027 G3 |
|---|---|---|
| Standalone Geography | K226 | K329 |
| Humanities (Social Studies, Geography) | K229 | K335 |
| Standalone History | K227 | K330 |
| Humanities (Social Studies, History) | K230 | K336 |
| Literature in English (standalone) | K228 | K331 |
| Humanities (Social Studies, Literature in English) | K231 | K337 |
These are real distinctions: not merely two spellings of the same paper. A student might do well explaining coastal processes or historical causation but still need to learn the response demands, evidence selection and citizenship-oriented reasoning of the Social Studies component when it is part of a Humanities subject.
A useful worked revision habit is to open the exact subject syllabus and make a checklist of the types of evidence a candidate must interpret: prose extracts, statistical diagrams, maps, photographs, statements, timelines, written accounts or other sources. The subject combination determines the relevance of each task.
When speaking to a school, avoid asking only ‘Does my child have Geography?’ Ask whether it is standalone Geography or part of Humanities (Social Studies, Geography), at which G-level, and under which examination code.
7. Chinese, Malay and Tamil: read the language and level
For ordinary Chinese Language in the 2027 school-candidate catalogues, the codes are G1 K120, G2 K220 and G3 K320. Equivalent distinctions appear across the other official Mother Tongue subjects. However, more specialised language pathways—including Higher Mother Tongue, third languages and language special programmes—may have different eligibility and national syllabuses.
Do not assume that one Chinese lesson, a Higher Chinese class and a third-language pathway all lead to one interchangeable examination. Nor should parents infer that oral and listening examinations are identical at every level simply because the language name is the same. The chosen syllabus sets the relevant assessment objectives and components.
The practical family question is what the learner is already doing well: understanding ordinary speech, organising written ideas, reading unfamiliar text or expressing a personal judgement? Strengthening the actual language capability is a worthwhile goal regardless of the exact code.
8. Computing: a new-syllabus example
Computing appears in the 2027 school-candidate directories as G1 K127, G2 K237 and G3 K349. The catalogues indicate the examined subjects and, in some instances, label revised or new syllabuses and make specimen resources available. These are important signs to check current content rather than assuming an older worksheet covers all examinable technology and skills.
A student may be able to create a Scratch project but still need practice explaining logic, managing data, testing a solution or using required software in an assessed context. Another student may have strong digital skills from a CCA yet not be registered for a Computing examination at all.
Use the code to identify the formal assessment, then ask the child to show what they can build and explain independently. In Computing, as in Mathematics, capability is visible when knowledge transfers to a fresh problem.
9. Art, Music, Design and Food: the code separates exploration from certification
Lower-secondary Art, Music, Design and Technology, and Food and Consumer Education form part of the broader experience of schooling. Upper-secondary examined electives are separately registered where offered. The 2027 SEAB directories list examined Art as G1 K126, G2 K236 and G3 K347. Higher Art is another G3 subject, K348; its requirements should be read separately.
For Design and Technology the codes include G1 K124, G2 K234 and G3 K345. Nutrition and Food Science uses G1 K125, G2 K235 and G3 K346. Music is listed as G1 K128 and G3 K350, with Higher Music G3 K351. Do not infer an unlisted G2 Music examination or confuse Higher Music with ordinary school music participation.
These differences matter because many creative and practical examinations have specifications beyond a conventional written-paper timetable. Coursework, project documentation, investigations, submission formats and other requirements must be confirmed in each official syllabus and the school’s own assessment instructions.
Families can learn more in our School Learning versus SEC Subjects article and the coursework/practical assessment guide. The important thing is to prepare for the correct assessed task, not merely collect art materials or repeat a written worksheet.
10. Applied subjects: the listing does not guarantee local availability
Certain subjects appear in official catalogues but have restricted school availability. The G1 list includes approved MOE–ITE Applied Subjects Mobile Robotics K130, Smart Electrical Technology K131 and Retail Operations K132. SEAB explicitly identifies these as applicable only to candidates from schools approved to offer them and states that 2027 is their final examination year.
The G3 school-candidate list separately identifies Biotechnology K375 and Design Studies K376 as approved-school Applied Subjects. The SEAB notes state that 2028 will be the last examination year for those G3 applied subjects. Those are different subject families with different phasing-out dates; they should not be merged into a single claim about ‘all applied subjects ending in 2027’.
A parent whose child wants a specialised programme should therefore ask two questions: is this a nationally examined 2027 subject, and is the child’s school approved to offer it to the relevant cohort? For details of school options, read why a national SEC subject does not mean every school offers it.
11. How to find the correct 2027 syllabus in five careful steps
- Write the exact subject title from the school. Note any brackets such as ‘(Physics, Chemistry)’ or ‘(Social Studies, History)’. Do not shorten the name before checking.
- Confirm the student’s G-level. It may differ across subjects within the same child’s timetable.
- Open SEAB’s 2027 school-candidate directory. Select the G1, G2 or G3 list. These are different from private-candidate pages.
- Match the precise subject and K-code. Check for Higher, standalone, combined, approved-school or revised-syllabus notes.
- Open the linked syllabus and check the assessment scheme. Confirm paper components, objectives, duration and applicable practical, oral or coursework requirements. Ask the school to confirm registration if anything differs.
As a simple test, suppose the school report says ‘Humanities (Social Studies, History)’ and the subject level is G3. The family should locate K336, not download the G3 standalone History K330 syllabus just because the word History is in both titles.
This routine can save hours of avoidable revision. It also helps teachers and tutors plan coherent lessons instead of teaching a topic that belongs to a different combination.
12. What does a ‘specimen paper’ mean?
SEAB’s catalogue provides specimen resources for revised syllabuses where available. A specimen paper is a reference illustrating the expected assessment style and may be useful for identifying formats or task demands. It is not a promise that every future question will look identical, and its publication year need not match the national examination year.
A parent should look for the syllabus document first. Read what is assessed and how the paper is organised, then use specimen questions as examples of those requirements. This guards against the common mistake of practising a paper style without understanding the skills that examiners are looking for.
Where copyrighted figures or materials are not reproduced in an online specimen, SEAB may provide descriptions or references instead. A missing image in a sample PDF is not evidence that the actual examination will omit visual materials.
13. Paper numbers, subject codes and component codes are different ideas
K310 refers to the whole examined G3 Mathematics subject, while Paper 1 and Paper 2 describe components within the assessment. A paper number is not a separate student admission stream or a second standalone SEC subject. Likewise, the letter K is not a code for a marks band.
A syllabus’s assessment scheme may specify papers with different durations, mark totals, formats, question choices or permitted aids. These details should be taken from the actual 2027 document. A parent who finds a Paper 1 from an older syllabus should not assume it has the same instructions as the new year’s paper.
For revision planning, make three columns: national subject code, component name, skill tested. For Mathematics the final column might include algebra, graphs or problem-solving; for languages it might include writing or oral communication; for a practical elective it might include investigation or project reporting.
14. How a code prevents a parent’s typical wrong-material purchase
Picture a parent shopping for revision books. The child studies G2 Humanities (Social Studies, Geography), but the cover of a workbook simply reads ‘Secondary Geography’. The parent buys it, and the child works through questions on familiar topics yet never practises the full range of source questions that the actual combined Humanities syllabus assesses.
Now apply a code-first check. The school confirms K229. The parent opens SEAB’s G2 syllabus and checks the subject combination, assessment structure and expected responses. They can then choose materials that match both the Geography and Social Studies components while retaining practice of general reading, writing and evidence skills.
The exact same method helps a parent avoid a Science workbook for the wrong combination. K224 is Physics and Biology, while K225 is Chemistry and Biology. Both include Biology, but the first paired discipline differs, so the revision plan cannot be identical.
A good purchase is therefore not the thickest or newest-looking book. It is the one that fits the student’s current assessed syllabus and clearly develops independent understanding.
15. Worked example: a learner’s four-subject planning sheet
Consider a hypothetical Secondary 4 student whose school has confirmed G3 English, G2 Mathematics, G2 Science (Chemistry, Biology) and G3 Humanities (Social Studies, Geography). The parents should not assign all four subjects one G-level because the student entered secondary school through a particular Posting Group.
| Subject on the confirmed record | Correct 2027 K-code | What to do next |
|---|---|---|
| G3 English Language | K300 | Open the G3 English assessment objectives and paper descriptions |
| G2 Mathematics | K210 | Use G2 Mathematics content and component specifications |
| G2 Science (Chemistry, Biology) | K225 | Prepare for the Chemistry and Biology combined syllabus |
| G3 Humanities (Social Studies, Geography) | K335 | Include the correct combined Humanities requirements |
Such a combination is illustrative only, not an endorsement of a particular school’s timetable or an assurance that every school can offer it. The school should confirm the actual entries. Once accurate, the sheet can be used to organise notebooks, past-year resources, tutoring, teacher questions and deadlines.
The student can now ask meaningful questions: which topics have I not mastered, which component needs a stronger explanation, and which skill would produce the greatest improvement with another week of careful practice? That is a much more constructive strategy than worrying about whether one code looks superior to another.
16. Do the codes themselves determine 2028 post-secondary admission?
No. A code identifies the subject and G-level. Post-secondary eligibility and score computations depend on the published rules for the intended programme and application route, alongside the candidate’s official results. The 2028 Post-Secondary Admissions Exercise is scheduled to consolidate applications for key pathways after the first SEC results.
For example, the fact that K232 and K341 are both Additional Mathematics subjects does not mean a particular future diploma has identical entry requirements for both. Do not guess a conversion or assume a G-level substitution without checking official admission guidance. The appropriate rules may depend on whether the applicant is considering JC, MI, polytechnic, PFP, ITE or a specific course.
It is wise to plan backwards from possible interests while leaving space for discovery. Students are still growing. They can strengthen a subject, explore career-related projects and learn from subject teachers without making every examination choice a permanent identity statement.
For a wider view, see all 2027 SEC subject families and 2028 routes and the 2027 SEC certificate reading guide.
17. A parent conversation that fixes confusion quickly
If the school’s subject naming or an old revision paper causes confusion, a short message to the subject teacher is often enough. Ask: ‘Could you confirm my child’s 2027 SEC subject title, G-level and K-code, and direct us to the examination syllabus?’ This is specific, respectful and straightforward for the school to answer.
Follow with one practical question: ‘Are there any revised components, coursework requirements or specimen resources we should use when preparing?’ That question makes the conversation about learning, not about paperwork for its own sake.
When the answer arrives, make sure the child has the same information. Show them how to locate the right syllabus themselves. The aim is to teach a durable skill: when official requirements matter, find the primary source rather than rely on an outdated screenshot or someone else’s summary.
Frequently asked questions
Are K110, K210 and K310 just different names for the same Mathematics paper?
No. They are the 2027 SEC national subject codes for G1, G2 and G3 Mathematics respectively. The exact requirements are found in the corresponding syllabus and its component specifications.
If my child is PG2, do all the examination codes begin K2?
Not necessarily. Posting Group describes the Secondary 1 posting route. Individual examination subjects may be taken at different G-levels under appropriate arrangements. Confirm each subject instead of assigning the same code prefix to a child’s whole timetable.
Can I use a 2026 O-Level 1184 paper to prepare for K300?
SEAB lists 1184 as the 2026-and-earlier reference code for 2027 G3 English Language K300. Such material may be useful when its content and formats remain relevant, but the 2027 syllabus should determine the actual preparation priorities.
Why is G3 standalone History K330 but G3 Humanities (Social Studies, History) K336?
Because they are separately listed national examined subjects. The Social Studies combination has its own subject structure. Use the code and full subject title to avoid practising the wrong set of assessed components.
What happens if the school offers a subject that I cannot find on SEAB’s SEC list?
It may be a lower-secondary common-curriculum subject, CCA, ALP, LLP, internally assessed school module or a programme with a different qualification route. Ask the school what it is called, whether it has national SEC assessment, and which syllabus applies.
Are private candidates allowed to register for everything listed for school candidates?
No such general entitlement should be assumed. SEAB maintains separate private-candidate subject directories, and eligibility or assessment availability can differ. Open the correct candidate-category list and follow SEAB registration guidance.
Does a higher-numbered code always mean the examination is more difficult?
The code is an identifier, not a calculated difficulty score. G-levels have different curriculum and assessment expectations, but numerical size alone is not a valid measurement of workload, outcomes or individual achievement.
Can a school ask a student to change G-level even after the subject appears on a report?
School subject-level arrangements and subsequent national registration are related but not identical. The school can explain its procedures, eligibility requirements and confirmation points. Use the latest official record for examination planning.
What if I find two different K-codes attached to the word ‘Geography’?
Read the complete subject title: standalone Geography is a different national examination entry from Humanities (Social Studies, Geography). Also check the G-level. The complete title, level and year resolve the ambiguity.
Do all 2027 national examinations have only written papers?
No. Paper arrangements vary: oral, listening, practical, laboratory, e-examinations and coursework can be relevant depending on subject and syllabus. Check the components of the actual K-coded subject.
A compact parent checklist to save
- I have the correct exam year: 2027.
- I know whether my child is a school candidate or private candidate.
- I know the G1, G2 or G3 level of each examined subject.
- I copied the complete subject title, including any bracketed combination.
- I matched the 2027 K-code on SEAB’s actual directory, not just an old paper cover.
- I checked the assessment scheme and relevant written, oral, practical or coursework components.
- I confirmed school availability and registration where necessary.
- I know where to find current admission guidance when post-secondary applications approach.
Continue reading across the eduKate education ecosystem
- School results versus national SEC grades
- Why some 2027 SEC subjects are not offered by every school
- Which school lessons become SEC examination subjects
- Secondary 2 to Secondary 3 subject combinations
- 2027 SEC registration and access arrangements
- How the 2027 SEC certificate records G-levels and grades
- 2027 SEC in-paper timing and question selection
Official SEAB source documents
- 2027 G1 SEC syllabuses for school candidates
- 2027 G2 SEC syllabuses for school candidates
- 2027 G3 SEC syllabuses for school candidates
- SEAB overview of the Secondary Education Certificate
- 2027 SEC G1 private-candidate directory
- 2027 SEC G2 private-candidate directory
- 2027 SEC G3 private-candidate directory
One accurate document can make learning much simpler
There is no advantage in rushing through a pile of wrongly matched past-year papers. Find the student’s actual 2027 syllabus first; understand the assessed skills; practise the required components; then revisit mistakes with a calm and thoughtful plan. The code is simply a tool that points to those requirements.
A child can enter secondary school through any Posting Group and make meaningful academic and personal progress. Precise information about the G-level and the examination subject helps families make good decisions, while a learner’s effort, growth, curiosity and future opportunities are far richer than any code.