The NEET chapters that carry the most marks are Molecular Basis of Inheritance, Biotechnology: Principles and Processes and Biomolecules in Biology; Optics, Electrostatics and Properties of Solids and Liquids in Physics; and Coordination Compounds, Organic Compounds Containing Oxygen and Redox Reactions and Electrochemistry in Chemistry. These come from TestBudy's NEET-UG chapter-wise weightage, measured across many years of past papers.
When is NEET 2027?
NTA has not announced the NEET-UG 2027 date yet. In past years the paper has usually been held on the first Sunday of May, but that is a pattern, not a date. The JEE Main and NEET exam dates page will show the date once NTA publishes it.
Planning around early May is sensible. Planning around one particular day is not, until NTA says which day it is.
How the NEET paper is built
NEET-UG is one paper of 180 questions for 720 marks, in 3 hours. Biology carries 90 of those questions, Physics 45 and Chemistry 45.
A correct answer earns 4 marks. A wrong answer costs 1 mark. A question you leave unanswered scores zero. That marking matters for how you prepare: a chapter you half know can cost you marks through wrong answers, not just fail to earn them.
The heaviest chapters, subject by subject
The table shows the three heaviest chapters in each subject. Each chapter name links to its page, where you can see its topics and practise it.
| Subject | Chapter | Share of subject | About questions | About marks |
|---|---|---|---|---|
| Physics | Optics | 8.9% | 4.0 | 16 |
| Physics | Electrostatics | 8.2% | 3.7 | 15 |
| Physics | Properties of Solids and Liquids | 7.5% | 3.4 | 14 |
| Chemistry | Coordination Compounds | 8.5% | 3.8 | 15 |
| Chemistry | Organic Compounds Containing Oxygen | 7.6% | 3.4 | 14 |
| Chemistry | Redox Reactions and Electrochemistry | 7.1% | 3.2 | 13 |
| Biology | Molecular Basis of Inheritance | 7.6% | 6.8 | 27 |
| Biology | Biotechnology: Principles and Processes | 5.7% | 5.1 | 20 |
| Biology | Biomolecules | 5.3% | 4.8 | 19 |
Here is how to read the three number columns.
Share of subject is the chapter's proportion of all the questions in its own subject, measured across past papers. The shares in one subject add up to 100%.
About questions is that share multiplied by the number of questions the subject has on the NEET paper. It is an average, which is why it is often a fraction. No paper has part of a question; a fraction means the chapter turns up in some years and not in others.
About marks is the expected number of questions multiplied by the marks for a correct answer.
Biology
The heaviest Biology chapters are Molecular Basis of Inheritance, Biotechnology: Principles and Processes and Biomolecules. Biology's marks are spread across many chapters, so even the heaviest ones are only part of the picture.
That spread changes how to prepare. Biology questions follow the NCERT textbook closely, often line by line. Reading a heavy chapter carefully, including its diagrams and tables, and then testing yourself on it is usually worth more than reading many chapters quickly.
Physics
The heaviest Physics chapters are Optics, Electrostatics and Properties of Solids and Liquids. Physics questions on NEET are mostly short numericals and concept checks. Knowing a formula is not enough; you need to apply it quickly and avoid unit slips.
For these chapters, work through a set of questions after each topic rather than at the end of the chapter. Mistakes in Physics tend to repeat, and catching them early saves you from practising them.
Chemistry
The heaviest Chemistry chapters are Coordination Compounds, Organic Compounds Containing Oxygen and Redox Reactions and Electrochemistry. Chemistry splits into physical, organic and inorganic parts, and each needs a different kind of practice: calculations for physical, reaction patterns for organic, and careful memory work from NCERT for inorganic.
Check which part each heavy chapter belongs to, and practise it in that way.
How to use this list
A list of heavy chapters is only useful if it changes what you do this week. A good way to use it:
- Take a chapter test on each heavy chapter in the table. Be honest about the result.
- Put the heavy chapters you scored poorly in at the top of your plan. These are where marks are most likely to be leaking.
- Fix them one or two at a time, then take a chapter test again to check the fix held.
- Once the heavy chapters are steady, move on to the next ones in the full weightage table.
Lighter chapters still matter. Some are short and quick to learn, and a few marks from an easy chapter count the same as marks from a hard one. Use the weightage to decide what to do first, not what to skip.
What weightage cannot tell you
Weightage is an average over many years. In any single paper a light chapter can appear more than usual, and a heavy one less. That is normal, and it is why the table is a starting point for a plan rather than a prediction.
Weightage also says nothing about you. A heavy chapter you already know well needs less of your time than a lighter one you keep getting wrong. The only way to know which is which is to test yourself, then look at where your marks actually went.
Frequently asked questions
Which NEET Biology chapters carry the most marks?
On TestBudy's NEET-UG weightage table, the heaviest Biology chapters are Molecular Basis of Inheritance, Biotechnology: Principles and Processes and Biomolecules. These are long-run averages over past papers, not a forecast of one paper.
Has NTA announced the NEET 2027 exam date?
Not yet. NEET-UG has usually been held on the first Sunday of May in past years, but NTA has not announced a date for 2027. The exam dates page will show it once NTA does.
What is the NEET exam pattern?
NEET-UG is one paper of 180 questions for 720 marks in 3 hours. A correct answer earns 4 marks, a wrong answer costs 1 mark, and an unanswered question scores zero.
Can I practise these chapters for free?
Yes. A free TestBudy account includes 5 tests, which you can use on chapter tests, subject papers or full mocks. Each one gives you a score and early topic feedback.
Try it on your own preparation
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