AssaySee what any site is built with, and the evidence behind every answer.
Click Assay on any page: a side panel lists what the site is built with — platform, framework, analytics, payments — each with a confidence hallmark and the exact signals behind it. Detection runs on your device and makes no network request.
Coming soon to the Chrome Web Store
There is no install link yet. This page will link to the Chrome Web Store when Assay is published.
Free to use. Pro is $39 paid once, or $5.99 a month with no commitment, taxes included. Free and Pro
What Assay does
For web developers, agencies, marketers and anyone who needs to know what a site runs on.
- Shows the headline stack first — platform, framework, UI kit, analytics, payments — then every technology it recognized, by category, with versions when the page shows them.
- Gives each answer a hallmark, Confirmed, Likely or Possible, with a score out of 100. “Why?” lists the exact script, meta tag or marker it found.
- Never makes an answer Confirmed from page variables alone, since any page can set them, and names hosting or a CDN only when the page itself shows it.
- Recognizes more than 350 technologies in 26 categories, and can wait 5 seconds and scan again to catch tools that load late.
- Copies a result as Markdown or downloads it as CSV or JSON, and keeps your last 5 scans.
What stays on your device
- Assay reads a page only when you click its icon or press its shortcut in that tab. Nothing runs in the background or when a page loads.
- Detection runs on your device and makes no network request. It reads technical markers, never the text of the page or of form fields.
- Your scans, notes and tags are stored in your browser. Scans made in a private window are never saved.
- “Scan open tabs” asks Chrome for access to all sites for that run only, and removes it as soon as the run ends.
- With Pro, license checks send your license key and a random installation id, never pages, addresses or results. Pro keeps working offline for up to 30 days after the last check.
Permissions
What Assay asks Chrome for, and why.
- At install
- None. Assay has no access to your websites until you click it.
- activeTab
- Reads the current page only after you click the Assay icon or press Alt+Shift+Y.
- scripting
- Runs Assay’s read-only detector in the tab you asked to scan. Nothing runs on other pages.
- sidePanel
- Shows the results next to the page.
- storage
- Saves your settings, your recent scans, the Pro notebook and your license status on this device.
- alarms
- Wakes about twice a day to re-check a Pro license when the last check is more than a day old, and removes the access of an interrupted “Scan open tabs” run.
- Access to all sites, optional
- Asked only when you start “Scan open tabs”, after Assay explains it, and removed as soon as the run ends.
Screens
Free and Pro
| Feature | Free | Pro |
|---|---|---|
| Scan the current page, with the evidence behind every answer, no limit | Included | Included |
| Rescan, and export a result as Markdown, CSV or JSON | Included | Included |
| Full JSON backup and restore | Included | Included |
| Scans kept | 5 | 1,000 |
| Notes and tags on each site | Not included | Included |
| Compare two scans, and group your sites by technology | Not included | Included |
| Export many sites at once | Not included | Included |
| Tabs per “Scan open tabs” run | 5 | 50 |
The free version has no limit on scans, and runs “Scan open tabs” once a day. The JSON backup stays free if Pro ends.
Assay Pro
- One-time purchase
- $39paid once
- Monthly
- $5.99a month
- The one-time purchase is a single payment: nothing renews. Updates are included.
- The monthly subscription renews every month until you cancel it. No commitment: cancel anytime from the customer portal, and Pro stays on until the end of the month you paid for.
- One license key covers up to 3 Chrome installations at a time, with either offer.
- Prices in US dollars, including any VAT or sales tax.