Guide · Founders
How to make a YC demo video
A YC application demo video should show your product working, start on the core action within the first few seconds and stay short: around one to two minutes is usually enough to prove it works. Show the real product doing the one thing users come for, narrate in plain words, and skip logos, slides and team intros. Check the current application form for its exact length and file-size limits before you export.
Key takeaways
- YC partners watch a lot of applications. Show the product doing its main job in the first 5 to 10 seconds.
- Real product beats mockups. If it's early, show the rough version that works.
- One user, one task, start to finish. Skip settings, sign-up and edge cases.
- The demo is separate from the founder video: the demo shows the product, the founder video shows the team.
- Read the current application form for its length and file-size limits; they can change between batches.
Why the demo matters
In How to Apply to Y Combinator, Paul Graham describes reading an application: after the description, he looks at the video and checks out the demo. On videos he notes, "Statistically we're much more likely to interview people who submit a video." A demo answers the question every reviewer has: does this thing exist and does it work?
What to show, in order
| Time | Show | Say |
|---|---|---|
| 0–10 s | The product already doing its main job | "This is [Product]. [User] uses it to [job]." |
| 10–50 s | One user completing one real task, start to finish | What they do and what they get, in plain words |
| 50–70 s | The result, plus one proof point | Usage, revenue, a customer, or what's live now |
| 70–90 s | Optional: the second most important flow | Only if it adds something the first one didn't |
Common mistakes
- Opening with a logo animation, a slide or a team introduction.
- Showing the sign-up flow before the product does anything.
- Narrating clicks ("now I click on settings") instead of outcomes.
- Polishing a mockup instead of showing the working product.
- Background music so loud the voice is hard to follow.
Write the script before you record, at about 147 words per minute of English. A 60-second demo is around 147 words; time yours with the script length calculator.
Frequently asked questions
How long should a YC demo video be?
Keep it short: one to two minutes usually proves the product works. Check the current application form for its exact limit before exporting.
What's the difference between the YC founder video and the demo?
The founder video introduces the team and is about the people. The demo shows the product working. Make both, and keep each focused on its job.
Should my YC demo have a voice-over?
Yes. A clear voice explaining what the user does and gets is easier to follow than silent footage or on-screen text alone.
Can I use an AI tool to make my YC demo?
Yes. Tools like ViralDub film and narrate your product from its URL. Review the result and make sure it shows the real, working product.
What if my product is very early?
Show the part that works, even if it's rough. If nothing is clickable yet, a short narrated walkthrough of mockups with an honest description is better than nothing.