From the outside, an accelerator looks like a short course with a cheque attached. Inside, it is a fixed sequence: you apply, a small group is chosen, the group works through the same weeks together, and the programme ends with every company pitching investors on the same day. The money arrives on standard terms that are the same for everyone in the cohort. This guide walks through each part and explains what the documents you sign actually say.
A cohort, a clock and a demo day
Yael Hochberg’s chapter for the National Bureau of Economic Research (2016) describes seed accelerators as fixed-term, cohort-based programmes that end in a public pitch event, or demo day. She also points out that accelerators bundle services founders used to find separately, each at a cost: early money, mentoring, introductions and a stage in front of investors. The chapter cites worldwide estimates of more than 3,000 programmes, without a date for the estimate, so treat it as an order of magnitude.
The sequence usually runs like this:
- Applications. A written form, often with a short video, then one or more interviews. Our guide on how to apply to an accelerator covers what programmes ask.
- Selection and the deal. Accepted companies sign the standard documents and receive the money, often at the start.
- The programme. Weeks of check-ins with the programme’s partners, mentor meetings, workshops and a steady push to show progress. Many programmes last about three months.
- Demo day. Every company presents to an audience of investors, usually on one day. See what a demo day is.
- Afterwards. The programme stays on your cap table, and the alumni network stays open.
How much of your week the programme takes varies. Some are full-time and in person for the whole term; others meet online once a week, or bring the cohort together for a few in-person sessions. Ask before you apply, because a programme that needs you in another city for three months is a different commitment from one you can do from home.
Because every company joins at once, programmes run on deadlines. Missing one usually means waiting for the next cohort, so check the deadlines page and each listing’s dates early.
The standard deal
Accelerators offer one set of terms to every company they accept, which is what makes a decision in days possible. Two well-known examples, both read on their own pages on 18 October 2026:
- Y Combinator invests US$500,000 in two parts, according to its standard deal page: US$125,000 on a post-money SAFE for 7% of the company, and US$375,000 on an uncapped SAFE with a most favoured nation (MFN) clause, which converts on the terms of the lowest-cap SAFE the company issues later.
- Techstars invests US$220,000, according to its investment terms page: US$20,000 through a post-money convertible equity agreement that becomes common stock equal to 5% of the company, including the existing option pool, at a priced round of at least US$1 million, plus US$200,000 on an uncapped MFN SAFE. The page notes different terms in Asia-Pacific.
The fixed part of each deal implies a valuation. US$125,000 for 7% values the company at US$125,000 ÷ 7%, or about US$1.79 million, once the money is in. That number is low by later standards, which is the point: the programme is pricing the risk of a company it has only just met.
The listings for Y Combinator and Techstars carry these terms with their sources, and the deal terms table puts every programme that publishes an offer side by side. Smaller programmes often invest less, some invest nothing, and a few charge a fee; our guide to red flags in accelerator terms covers what to watch for.
How SAFEs turn into shares
Most accelerator money arrives on a SAFE, a simple agreement for future equity: cash now in exchange for shares at the company’s next priced round. Y Combinator’s SAFE page says the company standardised on the post-money SAFE in 2018, and states the rule that makes it easy to read: the ownership you sell equals the investment divided by the valuation cap. The cap is “post” all the money raised on SAFEs, but not the priced round that follows, so that round dilutes the SAFE holder like everyone else.
Two consequences matter for founders:
- Every SAFE adds up. Each post-money SAFE takes its own fixed slice, and the slices come out of the founders’ share. Three SAFEs that each convert into 5% leave the founders with 15% less before the priced round starts.
- Uncapped MFN SAFEs float. With no cap of their own, they take the best terms of a later SAFE. The YC deal page gives an illustration: US$375,000 converting at a US$15 million cap would be 2.5%. Raise your next SAFE at a lower cap and the same money buys a larger stake.
Older SAFEs used a pre-money cap, which measures the valuation before the SAFE money comes in. The same cap then buys a slightly smaller stake, and each new SAFE dilutes the earlier ones, which is harder to follow. If a programme offers a pre-money SAFE or a discount-only SAFE, work out what it converts into before you compare it with a post-money offer.
The SAFE calculator shows what a SAFE converts into at its cap, with a discount and at a priced round you choose. The accelerator dilution calculator follows the founders’ stake from the accelerator’s investment through later rounds.
Pro rata and the rights that come with the money
The cheque is rarely the only thing you sign. Both deals above include rights that last well beyond the programme.
- Pro rata. The YC deal page says YC takes a right to keep investing in later rounds. Y Combinator’s SAFE page describes the pro rata right as optional and kept in a separate, standard side letter rather than in the SAFE itself. A pro rata right lets the investor buy enough of a new round to keep its percentage, which can take room your lead investor wanted.
- Other side-letter rights. The Techstars terms page says its side letter sets pro rata, digital-asset and drag-along rights. A drag-along right obliges a shareholder to join a sale the majority approves, which matters if the company is acquired.
- Information rights. Many investors ask for regular updates or accounts. These are normal, but check what you promise and how often.
Smaller programmes sometimes add terms the large ones do not: a right of first refusal on your next round, a board observer seat, a stake that tops up when you raise, or a fee taken out of the investment. If a term is not in the programme’s published deal, ask why it is in yours.
None of these is unusual, and standard documents exist precisely so founders do not have to negotiate them under time pressure. They are still worth reading before you sign. Ask the programme for every document in the deal, including side letters, and have a lawyer who acts for startups read them.
What you get besides the money
Founders rarely pick an accelerator for the cheque alone. What the programme adds is harder to price but often matters more:
- Pace. A fixed end date and regular check-ins force decisions that might otherwise drift for months.
- People. Partners and mentors who have seen hundreds of companies at your stage, plus a cohort of founders facing the same problems at the same time.
- Access. A demo day audience of investors who have chosen to come, and an alumni network that answers emails.
- Credibility. A known programme’s name can make a first sale or a first investor meeting easier.
How much of this you get depends on the programme and on you. Ask alumni from the last two or three cohorts what the partners actually did for them, how many investors came to demo day, and how many companies raised a round within six months. A programme that cannot point you to alumni willing to talk is telling you something.
Weigh those against the cost: the equity, the time, and sometimes a move to another city for the length of the programme. The time is easy to underrate; months of the founders’ full attention are the scarcest thing an early company has. If an equity-free programme or a grant is also on offer, the equity or equity-free calculator shows the exit value at which the equity becomes the more expensive money. Every accelerator we list is in the accelerators section, with its terms and dates.
Sources
Each page was read on the date shown. Figures in this guide carry the date the source gives them.
- Y Combinator: The Y Combinator standard deal. Undated page. Read 18 October 2026.
- Y Combinator: The SAFE: documents and how ownership is calculated. Undated page. Read 18 October 2026.
- Techstars: Techstars investment terms. Undated page. Read 18 October 2026.
- NBER, Innovation Policy and the Economy, volume 16 (Yael V. Hochberg): Accelerating Entrepreneurs and Ecosystems: The Seed Accelerator Model. Published March 2016. Read 18 October 2026.