Browser security
Compatibility & evidence
Transport and response hardening

Clear-Site-Data: storage

Requests clearing of browser-held storage in the scope of the response.

Support in current browsers

Checked against the current browser versions recorded in MDN browser data 8.1.5.

BrowserMinimumOutcomeReason
Chrome155WorksEvery required mapped BCD feature is available without a recorded qualification.
Edge154WorksEvery required mapped BCD feature is available without a recorded qualification.
Firefox157WorksEvery required mapped BCD feature is available without a recorded qualification.
Safari27WorksEvery required mapped BCD feature is available without a recorded qualification.
Chrome for Android155WorksEvery required mapped BCD feature is available without a recorded qualification.
Firefox for Android157WorksEvery required mapped BCD feature is available without a recorded qualification.
Safari on iOS27WorksEvery required mapped BCD feature is available without a recorded qualification.
Android WebView155WorksEvery required mapped BCD feature is available without a recorded qualification.
Samsung Internet30.0WorksEvery required mapped BCD feature is available without a recorded qualification.
The release trace

How support changed

Each segment groups recorded releases with the same result. Gaps between recorded versions are not filled in. This is support at each release, rather than the planner’s check of every release above a minimum.

Chrome

http.headers.Clear-Site-Data.storage
  1. 1 – 6060 recorded releases
    Not supported
  2. 61 – 15594 recorded releases
    Works

Edge

http.headers.Clear-Site-Data.storage
  1. 12 – 187 recorded releases
    Not supported
  2. 79 – 15475 recorded releases
    Works

Firefox

http.headers.Clear-Site-Data.storage
  1. 1 – 6265 recorded releases
    Not supported
  2. 63 – 15795 recorded releases
    Works

Safari

http.headers.Clear-Site-Data.storage
  1. 1 – 16.639 recorded releases
    Not supported
  2. 17 – 2722 recorded releases
    Works

Chrome for Android

http.headers.Clear-Site-Data.storage
  1. 18 – 6037 recorded releases
    Not supported
  2. 61 – 15594 recorded releases
    Works

Firefox for Android

http.headers.Clear-Site-Data.storage
  1. 4 – 6256 recorded releases
    Not supported
  2. 63 – 15785 recorded releases
    Works

Safari on iOS

http.headers.Clear-Site-Data.storage
  1. 1 – 16.636 recorded releases
    Not supported
  2. 17 – 2722 recorded releases
    Works

Android WebView

http.headers.Clear-Site-Data.storage
  1. 1 – 6032 recorded releases
    Not supported
  2. 61 – 15594 recorded releases
    Works

Samsung Internet

http.headers.Clear-Site-Data.storage
  1. 1.0 – 7.418 recorded releases
    Not supported
  2. 8.0 – 30.034 recorded releases
    Works

BCD 8.1.5 · catalogue 2.3.0. Source corrections can change this trace without a new browser release.

A fixed result snapshot

What those browser runs reported

Reviewed 11 October 2026

These are published results from specific stable-labelled browser builds. They are separate from the compatibility calculation and from evidence about your application. File outcomes and subtest counts stay separate. OK describes a completed harness, which can still contain failing subtests; Pass and Fail can also describe tests without a harness.

Selected directive tests: Clearing supported storage backends and removing service-worker control from an existing client.

The file includes setup checks and selects backends available in that browser. Its totals do not prove coverage of every storage mechanism, partition or application data flow.

Counts cover every subtest reported by each selected file, including any setup or complementary cases. They are not isolated directive pass counts or application evidence.

Exact browser builds, systems and source revision
  • firefox 157.0 · linux 22.04 · stable
    Run 4877098740350976 · 2026-10-06T10:36:34.451Z to 2026-10-06T11:50:28.028Z
    cc74d2669f5de548e808779877d1d33339ec5115
  • safari 27.0 (22625.1.29.11.27) · mac 27.0 · stable
    Run 5164107446878208 · 2026-10-06T06:14:03.64Z to 2026-10-06T09:13:55.471Z
    cc74d2669f5de548e808779877d1d33339ec5115
  • chrome 154.0.8037.92 · linux 22.04 · stable
    Run 6218298311311360 · 2026-10-06T07:44:01.102Z to 2026-10-06T11:57:16.569Z
    cc74d2669f5de548e808779877d1d33339ec5115

“Stable” is the upstream run label. Complete runtime flags were not supplied by the summary API. These results do not cover every browser version, mobile platform or operating system.

Storage clearing and service-worker control

clear-site-data

1 of 1 selected test files have retained results. The parent directory contains 15 retained files from 31 returned search matches. Only the exact files listed below enter these totals.

Browser buildSubtests passed / reportedFile outcomes
firefox
157.0		6 / 81 Timeout
safari
27.0 (22625.1.29.11.27)		8 / 81 OK
chrome
154.0.8037.92		10 / 101 OK
Read all 1 retained file results
Test filefirefoxsafarichrome
storage.https.htmlTimeout · 6/8 subtestsOK · 8/8 subtestsOK · 10/10 subtests

Source API query (whole directory)Test source at the run revision

Source-response fingerprintSHA-256 4dbadd51a6517e6aadc8708bbd8aa45873a7e80719fcf354a491ba4c6d8c63d0

The digest identifies the complete downloaded directory response used for this projection, before file selection. It does not authenticate the runner or prove that the results are truthful.

What this feature can and cannot do

Helps protect against

  • Residual client state after logout or reset

Does not guarantee

  • Server-side sessions
  • Data outside the directive's scope
  • Confirmation that clearing completed

What you need before using it

  • Secure-context delivery
  • A deliberate logout or reset flow
  • Review of effects on related applications

Fallback to keep in place

Invalidate server sessions and explicitly clear application state in the logout flow.