Find the barriers.Make way.
Six tools for auditing, understanding, and fixing web accessibility.
All six are free to use. Audit has an optional $99/yr Supporter tier.
For the people who design, build, and audit the web.
Your Accessibility Toolkit
Vesper Audit: Every finding.Tied to a fix.
Point it at any URL. Audit runs WCAG 2.2 Level A and AA checks and writes a structured report that names the page, the element and the criterion for each issue.
Single page scans are free. Full site crawls and PDF, Markdown, CSV, and Notion exports are Supporter features.
For consultants, agencies, and in-house teams. Requires macOS and Google Chrome.
✓ yoursite.org/
✓ yoursite.org/about
⚠ yoursite.org/contact 3 violations
✓ yoursite.org/events
→ Checking for broken links…
→ Exporting report…
Vesper Colors: Every color.Every pair.
Build and share palettes, open a full profile for any color, check any two colors against WCAG 2.2 AA and AAA, and simulate the four common types of color blindness.
It runs in the browser with nothing to install, and the same checker travels as a Mac menu bar app, an iOS app and a Chrome extension.
Get It Now
Learn More
Explore Vesper Colors: features and docsFor designers choosing colors before audit time.
Contrast ratio
Vesper Inspect: Hover anything.See everything.
Surface an element's ARIA label, role, computed name, alt text, heading level, tab order and image weight in an overlay that follows your cursor.
The header turns green, amber, or red by what it finds, so a problem announces itself before you go looking for one.
Get It Now
For developers, designers, and content teams spot-checking a page.
Alt textMissing
ARIA labelNone
Roleimg (implicit)
Tab orderNot focusable
ElementImage
File size1.4 MB
Vesper Mosaic: Three widths.One motion.
One URL loaded into three viewports at once, 390, 768 and 1920 pixels wide. Scrolling, clicking, and navigation stay in sync across all three.
Three fixed widths, one reload button, and no device-profile library to configure. Useful evidence for WCAG 1.4.10 Reflow.
Get It Now
Learn More
Explore Vesper Mosaic: features and docsFor developers and auditors checking responsive layout.
Vesper Orbit: Point it once.Walk away.
Orbit crawls a domain breadth-first and downloads every PDF, image, audio file and video into a clean per-site folder, with a manifest CSV.
It walks the site through a real Chrome, so it catches what wget and curl miss: og:image, picture srcset, and anything a script writes in.
Get It Now
Learn More
Explore Vesper Orbit: features and docsFor librarians, archivists, and researchers capturing site media.
Works with Audit
PDFboard-minutes-2026-03.pdf1.2 MB
PDFannual-report-2025.pdf4.8 MB
JPGarchive-photo-0114.jpg780 KB
PNGdistrict-map-north.png2.1 MB
MP3public-meeting-0412.mp318 MB
91 of 142 · writing manifest.csv
Vesper Guides: Know the why.Then the how.
Plain-language guides on WCAG, ARIA, and accessible design. One concept each, written for web teams rather than specialists.
What the failure is, why it matters to the person it affects, and how the fix looks in HTML. Audit findings link straight into them.
Get It Now
For anyone explaining a finding or implementing a fix.
Works with Audit
Writing effective alt text
Alt text is a translation, not a description. Good alt text carries purpose and context, not visual appearance. A photo of a dog running on a beach is not “image.jpg”, it is “Golden retriever chasing a wave at low tide”.
Heading structure
Six tools.One workflow.
Audit finds it. Colors, Inspect, and Mosaic verify the fix. Orbit collects the source files. Guides explains why.