How much equity a technical cofounder gets should come from full-time commitment, risk taken, and what each of you brings to the company, not from who thought of the idea first. Most pairs end up somewhere between an even split and a moderate lean toward whoever is building the product full time, and the right number for you depends on your specific situation.
How much equity does a technical cofounder usually get?
There is no standard percentage, whatever a quick search tells you. Y Combinator's own guidance argues for equal or near-equal splits in most cases, on the logic that it takes years to build something valuable and a small head start in month one should not set a permanent imbalance. Where pairs do lean unequal, the technical cofounder is usually the one building full time while the other still has a day job or another source of income, and the split tilts toward whoever is carrying the risk.
Does having the idea entitle you to more equity?
Mostly no. Y Combinator's position is direct: unequal splits that reward whoever had the idea, started a few weeks earlier, or took a smaller salary tend to be a mistake, because none of those predict who will actually build the company. The idea is the easy part. The technical cofounder turning it into a working product, and keeping it working for years, is where the value comes from. If you are the idea person and not writing code or managing the build, be honest with yourself about what you are actually contributing from month two onward.
What factors should actually move the split?
Treat these as inputs, not a formula. Sit down together and go through each one honestly.
| Factor | Why it matters |
|---|---|
| Full-time vs. part-time | Someone working on the company for a salary elsewhere is taking less risk than someone who quit their job for it |
| Who is building the product | The person writing the code, day after day, is creating most of the ongoing value |
| Capital or revenue already in | Money raised or customers signed before a cofounder joined should count toward whoever already built that, not get split as if both of you started at zero |
| Replaceability | A skill set you could hire for is worth less equity than one that is hard to replace |
| Prior IP or working code | Code or designs the technical cofounder brings in should be assigned to the company, and valued |
Y Combinator's advice to technical founders is blunt about one pattern: technical cofounders often end up with less than they are worth, because they underestimate how much of the company's long-term value runs through them. If you are the technical cofounder, do the math on what you are actually taking on before you agree to a number.
Is a 50/50 split a mistake here?
Not by default, but it only holds up under specific conditions: both of you are full time, both are taking comparable risk, and neither of you is easily replaced by a hire. Our guide on fair versus equal equity splits walks through when even splits work and when they quietly set up resentment. A flat 50/50 split between a technical cofounder building full time and a non-technical cofounder still drawing a salary elsewhere is the version that tends to cause trouble eighteen months in, once the gap in day-to-day contribution becomes obvious to both of you.
How do you protect the split once you've agreed on it?
Write it down, with a vesting schedule attached. A standard structure is four years with a one-year cliff, so equity is earned over time rather than handed over on day one regardless of what happens next. Our complete guide to splitting cofounder equity covers the mechanics in more detail, and the founders agreement templates are a faster starting point than drafting from nothing.
The number you land on matters less than the process you used to get there. Two cofounders who can both explain, a year later, why the split is what it is tend to stay aligned. Two who never actually talked about it, and let one person's assumption become the default, are the ones who end up renegotiating under pressure. If you want to find out where you and your cofounder already agree and where you do not, our free alignment check surfaces the gap before it becomes a dispute.
Frequently asked questions
- How much equity should a technical cofounder get?
- There is no fixed number. Most pairs land somewhere between an even split and a moderate lean toward whoever is full time and building the product, usually in the 40 to 60 percent range for the technical cofounder. The honest answer is that it depends on commitment, risk taken, and what each person actually contributes, not a formula.
- Does having the idea mean you deserve more equity?
- No, not on its own. An idea with no one building it is worth very little. What creates value is the years of work that turn the idea into a product people pay for, and that work is usually split closer to evenly than founders expect when they start from the idea alone.
- Is a 50/50 split a mistake for a technical and non-technical cofounder?
- Not automatically, but it only works if both of you are full time, equally committed, and equally replaceable. If one of you takes a salary while the other does not, or one owns the only skill the company depends on, a flat 50/50 split can store up resentment that surfaces later, usually at the worst time.
- What should we do instead of guessing at a number?
- Write down the factors that actually apply to your situation, agree on them together, and put the resulting split and the vesting schedule in a signed document. The number matters less than both of you agreeing on how you got there and being able to point back to it later.