Cookie ITP & 3P Block Checker
Paste a Set-Cookie list — see which cookies survive Safari ITP, which Chrome will cap, and which are flat-out third-party blocked.
Used to decide first- vs third-party.
Healthy
1
ITP-limited
3
3P blocked
1
_ga
ITP-limited (1P JS)_ga=GA1.2.123456789.1700000000; Domain=.example.com; Path=/; Max-Age=63072000; SameSite=Lax
- · First-party but client-side (no HttpOnly) — Safari ITP caps lifetime to 7 days regardless of Max-Age.
- · Lifetime > 400 days — Chrome (since 100) caps to 400 days for first-party cookies set via Set-Cookie.
_fbp
ITP-limited (1P JS)_fbp=fb.1.1700000000.123456789; Domain=.example.com; Path=/; Max-Age=7776000; SameSite=Lax
- · First-party but client-side (no HttpOnly) — Safari ITP caps lifetime to 7 days regardless of Max-Age.
ads_session
Blocked / restrictedads_session=abc123; Domain=.advertiser.com; Path=/; Max-Age=2592000; Secure; SameSite=None
- · Third-party cookie — blocked by Safari ITP and most ad blockers; partially restricted in Chrome.
session
Short-lived 1Psession=opaque; Path=/; Max-Age=86400; HttpOnly; Secure; SameSite=Lax
_gcl_au
ITP-limited (1P JS)_gcl_au=1.1.123.987; Domain=.example.com; Path=/; Max-Age=7776000
- · First-party but client-side (no HttpOnly) — Safari ITP caps lifetime to 7 days regardless of Max-Age.
- · No SameSite attribute — defaults to Lax in modern browsers.
