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UserProof / YC homepage check / Canary

Canary homepage check

Checked October 28, 2026 · Winter 2026 · runcanary.ai

75out of 100 · Fair · #322 of 378

Canary (Adversarial AI that breaks your AI) scored 75 out of 100 on our homepage check, #322 of 378 YC startups and #55 of 59 in Winter 2026. It passed 7 of 9 checks we could run. The biggest problem: we found no sign-up, demo or get-started button on the phone version of the home page.

Canary home page on a phone
Canary on a 390px phone, October 28, 2026. Outlined: “BENCHMARK 15 MIN READ · MARCH 2026 QA-Bench v0: measuring how AI models handle c”, the button we tested.
  • Fail
    A sign-up, demo or get-started button on the first phone screen (−20 points)We found no sign-up, demo or get-started button on the phone version of the home page.67% of YC startups pass this.
  • Pass
    The main button does something when tapped“BOOK A CALL” opens https://cal.com/runcanary/sales.99% of YC startups pass this.
  • Pass
    Nothing covers the main buttonNothing sits on top of it.96% of YC startups pass this.
  • Not tested
    The main button is at least 44px tall on a phoneNot tested: no clear main button on the phone version.65% of YC startups pass this.
  • Pass
    The page fits a phone screenNo sideways scrolling on a 390px-wide phone.100% of YC startups pass this.
  • Fail
    No JavaScript errors from the site's own code (−5 points)The site's own code threw an error: Minified React error #418; visit https://react.dev/errors/418?args[]=text&args[]= for the full message or use the non-minified dev environme95% of YC startups pass this.
  • Pass
    No broken links to the site's own pages10 internal links checked.97% of YC startups pass this.
  • Pass
    Everything that looks clickable respondsClickable things on 3 pages responded.90% of YC startups pass this.
  • Pass
    Loads in under 4 seconds on desktop and 6 on a phoneLoaded in 2.6s on desktop and 2.2s on a phone.75% of YC startups pass this.
  • Pass
    Images and files loadEverything we requested from the site loaded.92% of YC startups pass this.

How Canary compares

Canary is the outlined dot. The top row is all 378 YC startups we checked; the bottom row is Winter 2026.

Score
All startups378 sites
Canary: 75/100
Canary: 75/100
Winter 202659 sites

Good (90+)Fair (75-89)Needs work (0-74)Each dot is one startup. Tap a dot to see its page.

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Other Winter 2026 startups with similar scores

← #322 Bluebook · #322 CatchBack Cards → · All 378 scores

How we checked

We loaded the home page in Chromium as a 390px phone and a 1366px desktop, found the main button by its words (sign up, book a demo, get started and similar), tapped it once, and checked up to 3 pages for broken links and dead taps. Nothing was submitted. Each failed check costs the points shown. Full method.