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Antigen homepage check

Checked October 28, 2026 · Fall 2025 · antigen.sh

90out of 100 · Good · #192 of 378

Antigen (Continuous offensive security for the enterprise) scored 90 out of 100 on our homepage check, #192 of 378 YC startups and #21 of 39 in Fall 2025. It passed 8 of 10 checks. The biggest problem: 1 broken link, e.g. https://antigen.sh/trust returns 404.

Antigen home page on a phone
Antigen on a 390px phone, October 28, 2026. Outlined: “Get a demo”, the button we tested.
  • Pass
    A sign-up, demo or get-started button on the first phone screen“Get a demo” is on the first screen.67% of YC startups pass this.
  • Pass
    The main button does something when tapped“Get a demo” opens https://cal.com/team/antigen/demo.99% of YC startups pass this.
  • Pass
    Nothing covers the main buttonNothing sits on top of it.96% of YC startups pass this.
  • Pass
    The main button is at least 44px tall on a phone40px tall on a phone.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.
  • Fail
    No broken links to the site's own pages (−5 points)1 broken link, e.g. https://antigen.sh/trust returns 404.97% 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 0.9s on desktop and 1.7s on a phone.75% of YC startups pass this.
  • Fail
    Images and files load (−5 points)Https://antigen.sh/trust?_rsc=SNNi7CpTHafwwF0l returns 404.92% of YC startups pass this.

How Antigen compares

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

Score
All startups378 sites
Antigen: 90/100
Antigen: 90/100
Fall 202539 sites
Absurd: 100/100Alder: 100/100Clad Labs: 100/100Compyle: 100/100Digipals: 100/100Imagine AI: 100/100Mixy: 100/100MOVEdot: 100/100Uplane: 100/100Zalos: 100/100AnswerThis: 95/100AtlasGrid: 95/100Casey: 95/100Hyperspell: 95/100MadeThis: 95/100MarkIt: 95/100Metorial: 95/100Nessie: 95/100Patent Watch: 95/100Pixley AI: 95/100Brickanta: 90/100Expected Parrot: 90/100Kestrel AI: 90/100Parse: 90/100Semble: 90/100Bron: 80/100Caddy: 80/100Freeport Markets: 80/100Karumi: 80/100Koyal: 80/100Lua Global Inc: 80/100Sava Trust Company: 80/100Scott AI: 80/100Specific Labs: 80/100Aspect: 75/100Fifth Door: 75/100hillclimb: 75/100Sciloop: 75/100Antigen: 90/100
Absurd: 100/100Alder: 100/100Clad Labs: 100/100Compyle: 100/100Digipals: 100/100Imagine AI: 100/100Mixy: 100/100MOVEdot: 100/100Uplane: 100/100Zalos: 100/100AnswerThis: 95/100AtlasGrid: 95/100Casey: 95/100Hyperspell: 95/100MadeThis: 95/100MarkIt: 95/100Metorial: 95/100Nessie: 95/100Patent Watch: 95/100Pixley AI: 95/100Brickanta: 90/100Expected Parrot: 90/100Kestrel AI: 90/100Parse: 90/100Semble: 90/100Bron: 80/100Caddy: 80/100Freeport Markets: 80/100Karumi: 80/100Koyal: 80/100Lua Global Inc: 80/100Sava Trust Company: 80/100Scott AI: 80/100Specific Labs: 80/100Aspect: 75/100Fifth Door: 75/100hillclimb: 75/100Sciloop: 75/100Antigen: 90/100

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 Fall 2025 startups with similar scores

← #192 Adside.ai · #192 assistant-ui → · 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.