methodology / Modern Web / #67
Web App Manifest (manifest.json)
#67 · Variable · Web Quality · weighted · Modern Web · weight 0.7% · impl implemented · method v1.2.0
Web Quality factor
This factor is part of Web Quality — the weighted 0..100 score that sits above Web Standards. Its weight depends on what kind of site is being measured. Web Standards items take priority; this factor only enters the score once Web Standards passes.
- Base weight
- 0.3 applied to every site type unless overridden below
- Why this weight
- Web App Manifest — only relevant if the site is app-like or installable. Corporate dropped to 0.1 — most corporate marketing sites are read-only landing pages where a manifest adds nothing for the visitor.
Per-site-type overrides
| Site type | Weight | Δ vs base |
|---|---|---|
| Blog | 0.2 | -0.1 |
| E-commerce | 0.7 | +0.4 |
| Corporate / B2B | 0.1 | -0.2 |
| News / Publisher | 0.5 | +0.2 |
| Personal site | 0.1 | -0.2 |
| SaaS / Product | 0.9 | +0.6 |
| Media / Streaming | 0.5 | +0.2 |
Site types not listed inherit the base weight.
What this means for your business
When this is set up, customers who use your site often can pin it to their home screen like an app — which keeps you a tap away instead of buried in a search. It's a small file, but a missing one signals an older build.
Plain title: Your site can be saved to a phone's home screen
What we measure
A Web App Manifest lets users "Add to Home Screen" on mobile, treating your site like a native app with its own icon and splash screen.
How to improve your score
Generate one with any PWA generator and link it from your `<head>` with `<link rel="manifest" href="/manifest.json">`.
Facts
Implementation notes
Probe `/manifest.json` and parse the `<link rel="manifest">` href.
When this applies
Web App Manifest is graded for app-like and product sites.
- Marked n/a for site types: Personal site, Blog.
Scoring
Scoring formulas are versioned with the methodology. The current method (v1.2.0) maps raw measurements to pass, warn, fail. Factor weights determine how much each contributes to the composite — see the methodology index for the full table.
Version history
| Version | Change | Date |
|---|---|---|
| v1.2.0 | Factor introduced. Status: live. Scoring impl: implemented. | 2026-04-25 |