Guide · Hackathons
How to make a hackathon demo video judges remember
A hackathon demo video should show your working project in the first 10 seconds, explain the problem and what you built in plain words, and fit the organizer's limit, which is usually somewhere between 2 and 5 minutes. Devpost doesn't set one rule for every event, so read your hackathon's page first for the length cap and where the video must be hosted.
Key takeaways
- Rules beat tips: the length cap, the hosting site and what must be shown come from your hackathon's page, and judges can skip what runs over.
- Open on the project working. Judges watch dozens of videos and decide fast.
- Two minutes of English narration is about 294 words. Write it before you record.
- Show one or two real flows end to end, then say how it's built and what's new about it.
- Upload early: YouTube needs time to process HD, and a broken link at the deadline costs the whole entry.
Read the rules before you record
- Length: most events cap the demo at 2, 3, 4 or 5 minutes. Some judges stop watching at the limit.
- Hosting: usually a public or unlisted YouTube or Vimeo link pasted into the Devpost submission form.
- What to show: some events require the app running on a real device, or ban slides-only videos.
- AI and third-party assets: check whether AI voice-over, stock music or AI-generated visuals are allowed and whether you must disclose them.
A 2-minute structure judges can follow
| Time | Show | Say |
|---|---|---|
| 0–10 s | The project already doing its main job | "This is [name]. It [does the job] for [who]." |
| 10–25 s | The problem: the old way, a screenshot, a stat you can source | Why it matters, in one or two sentences |
| 25–90 s | One or two real flows, start to finish | What the user does and what they get |
| 90–110 s | Architecture diagram or the key piece of code | How it's built and what was hard or new |
| 110–120 s | Team, or what's next | One line each; no long thank-yous |
Recording fast, at 3 a.m.
- Write the script first and read it aloud with a timer. Cut until it fits with a few seconds spare.
- Seed the demo with realistic data. "test test 123" makes a good project look unfinished.
- Record each flow as its own clip so one mistake doesn't mean redoing everything.
- Record at 1920×1080, zoom the browser to about 125% and hide notifications and bookmarks.
- Use the best microphone you have and a quiet room. Clear audio matters more than fancy visuals.
- Add captions: judges often watch muted while scoring.
- Upload at least an hour before the deadline and open the link in a private window to check it plays.
Mistakes that cost points
- Spending the first 30 seconds on the team, the logo or the hackathon theme.
- Showing code before showing what it does.
- Narrating clicks ("now I click the button") instead of outcomes.
- Hiding what doesn't work. Say plainly what's mocked; judges respect honesty more than smoke and mirrors.
- Music louder than the voice.
Frequently asked questions
How long should a hackathon demo video be?
As long as your event allows and no longer: limits are usually 2 to 5 minutes. If there's no limit, aim for about 2 minutes.
Where do I upload a Devpost demo video?
Usually to YouTube or Vimeo, as a public or unlisted video, and then paste the link into the submission form. Check your hackathon's rules for the accepted sites.
Should I show code in a hackathon demo video?
Briefly, after showing the product working. A diagram or the one clever piece of code is enough; judges can read the repo.
Can I use an AI voice-over in a hackathon video?
Usually yes, but check the event's rules and disclose it if they ask. A clear AI voice beats a rushed, mumbled recording.
What if my project doesn't fully work?
Show the parts that do, and say clearly what's mocked or unfinished. Judges reward honest, working slices over a polished fake.