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UserProof / YC homepage check / Lark

Lark homepage check

Checked October 28, 2026 · Summer 2025 · getlark.ai

75out of 100 · Fair · #322 of 378

Lark (The E2E testing layer for AI-driven development) scored 75 out of 100 on our homepage check, #322 of 378 YC startups and #38 of 47 in Summer 2025. It passed 8 of 10 checks. The biggest problem: “Create account” is 852px down the page on a phone, below the first screen.

Lark home page on a phone
Lark on a 390px phone, October 28, 2026. Outlined: “Create account”, the button we tested.
  • Fail
    A sign-up, demo or get-started button on the first phone screen (−20 points)“Create account” is 852px down the page on a phone, below the first screen.67% of YC startups pass this.
  • Pass
    The main button does something when tapped“Create account” opens https://dashboard.getlark.ai/login.99% of YC startups pass this.
  • Pass
    Nothing covers the main buttonNothing sits on top of it.96% of YC startups pass this.
  • Fail
    The main button is at least 44px tall on a phone (−5 points)"Create account" is 38px tall on mobile (under 44px is easy to miss).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.
  • Pass
    No JavaScript errors from the site's own codeNone seen while loading and tapping the main button.95% of YC startups pass this.
  • Pass
    No broken links to the site's own pages7 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 2.2s on desktop and 1.3s 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 Lark compares

Lark is the outlined dot. The top row is all 378 YC startups we checked; the bottom row is Summer 2025.

Score
All startups378 sites
Lark: 75/100
Lark: 75/100
Summer 202547 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 Summer 2025 startups with similar scores

← #322 Juxta · #322 Manicule → · 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.