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Ossus homepage check

Checked October 28, 2026 · Winter 2026 · ossus.com

100out of 100 · Good · #1 of 378

Ossus (Intelligence for cultural institutions) scored 100 out of 100 on our homepage check, #1 of 378 YC startups and #1 of 59 in Winter 2026. It passed 7 of 7 checks we could run.

Ossus home page on a phone
Ossus on a 390px phone, October 28, 2026. Outlined: “Book a meeting”, the button we tested.
  • Not tested
    A sign-up, demo or get-started button on the first phone screenNot scored: the button we found on a phone was inside a closed menu.67% of YC startups pass this.
  • Pass
    The main button does something when tapped“Book a meeting” responds.99% of YC startups pass this.
  • Not tested
    Nothing covers the main buttonNot scored: the button we found sat inside a closed menu.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.
  • 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 pages21 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 1.8s 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 Ossus compares

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

Score
All startups378 sites
Ossus: 100/100
Ossus: 100/100
Winter 202659 sites
Cofia: 100/100Forum: 100/100Instinct: 100/100Kita: 100/100Oxus: 100/100Reframe: 100/100SpotPay: 100/100TensorTest: 100/100Vector Legal: 100/100Velum Labs: 100/100Verdex: 100/100VOYGR: 100/100Anchorhead: 95/100Ashr: 95/100Aurorin CAD: 95/100AutoSitu: 95/100FullSeam: 95/100LegalOS: 95/100Maven: 95/100Palus Finance: 95/100Pax Historia: 95/100Samora AI: 95/100shortkit: 95/100Sila: 95/100Zatanna: 95/100Zymbly: 95/100Cajal: 90/100Cardinal: 90/100Caretta: 90/100End Close: 90/100Fed10: 90/100Fenrock AI: 90/100Fort: 90/100Grade: 90/100Haladir: 90/100MochaCare: 90/100Pollen: 90/100Proximitty: 90/100Wideframe: 90/100Avoice: 85/100Balance: 85/100Robby: 85/100/dev/fast: 80/100Axis: 80/100Byteport: 80/100Envariant: 80/100Mantis: 80/100Ressl AI: 80/100SideKit: 80/100Sponge: 80/100Synthetic Sciences: 80/100Traverse: 80/100Visibl Semiconductors: 80/100Canary: 75/100CatchBack Cards: 75/100CodeWisp: 75/100The Token Company: 75/10021st: 70/100Ossus: 100/100
Cofia: 100/100Forum: 100/100Instinct: 100/100Kita: 100/100Oxus: 100/100Reframe: 100/100SpotPay: 100/100TensorTest: 100/100Vector Legal: 100/100Velum Labs: 100/100Verdex: 100/100VOYGR: 100/100Anchorhead: 95/100Ashr: 95/100Aurorin CAD: 95/100AutoSitu: 95/100FullSeam: 95/100LegalOS: 95/100Maven: 95/100Palus Finance: 95/100Pax Historia: 95/100Samora AI: 95/100shortkit: 95/100Sila: 95/100Zatanna: 95/100Zymbly: 95/100Cajal: 90/100Cardinal: 90/100Caretta: 90/100End Close: 90/100Fed10: 90/100Fenrock AI: 90/100Fort: 90/100Grade: 90/100Haladir: 90/100MochaCare: 90/100Pollen: 90/100Proximitty: 90/100Wideframe: 90/100Avoice: 85/100Balance: 85/100Robby: 85/100/dev/fast: 80/100Axis: 80/100Byteport: 80/100Envariant: 80/100Mantis: 80/100Ressl AI: 80/100SideKit: 80/100Sponge: 80/100Synthetic Sciences: 80/100Traverse: 80/100Visibl Semiconductors: 80/100Canary: 75/100CatchBack Cards: 75/100CodeWisp: 75/100The Token Company: 75/10021st: 70/100Ossus: 100/100

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 Winter 2026 startups with similar scores

← #1 Orchestra · #1 Oxus → · 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.