HTTP Strict Transport Security
Tells supporting browsers to use HTTPS for a host during a declared period.
Support in current browsers
Checked against the current browser versions recorded in MDN browser data 8.0.7.
| Browser | Minimum | Outcome | Reason |
|---|---|---|---|
| Chrome | 150 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Edge | 150 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Firefox | 152 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Safari | 26.5 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Chrome for Android | 150 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Firefox for Android | 152 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Safari on iOS | 26.5 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Android WebView | 150 | Works | Every required mapped BCD feature is available without a recorded qualification. |
| Samsung Internet | 29.0 | Works | Every required mapped BCD feature is available without a recorded qualification. |
What this feature can and cannot do
Helps protect against
- HTTP downgrade
- Accidental insecure navigation
Does not guarantee
- First-visit downgrade before policy is known
- TLS defects
- Certificate compromise
What you need before using it
- Reliable HTTPS
- A carefully chosen host and subdomain policy
Fallback to keep in place
Redirect HTTP to HTTPS and remove insecure links while assessing preload separately.