What is Privacy Sandbox?
What was Privacy Sandbox meant to do?
Websites and ad platforms have long used third-party cookies: small files that let one company recognise a visitor across other companies' sites. Privacy Sandbox set out to offer alternatives to them in Chrome. Then the plan changed course.
What is the status today?
Two steps changed the picture. In April 2025 Google said Chrome would keep offering users third-party cookie choice as before, with no new standalone prompt, and that the Sandbox APIs may have a different role to play1.
In October 2025 Google retired several Privacy Sandbox APIs and kept a few others, among them CHIPS, FedCM and Private State Tokens, according to a server-side tracking vendor's timeline2.
So Privacy Sandbox is no longer a plan to build on as a whole. If a tool or a plan names one of its APIs, check that API's status in Google's developer documentation.
Does it matter for your tracking?
Only partly. Browsers also limit tracking on their own, for example under Intelligent Tracking Prevention in Safari. Your measurement already has to work without relying on one browser's cookie rules.
What holds up is your own foundation: first-party data you collect directly, and server-side tracking that passes it to analytics and ad platforms. A tracking plan that depends on a single Sandbox API depends on something Google has already started to retire.
This is one of the checks in an ecommerce tracking audit.
For ZFD: Our view is that a tracking plan should not rest on a browser API its maker can retire.
Easily confused with
Privacy Sandbox vs The end of third-party cookies
Privacy Sandbox was the proposed replacement. The two are not the same event.
Privacy Sandbox vs Intelligent Tracking Prevention
Safari's rules to limit cross-site tracking. Different browser, different mechanism.
Buzzword alert
"We are Privacy Sandbox ready"
Usually means: work done for APIs whose role Google later changed.
Ask: what did "ready" change in our setup, and is any of it still running?
"Privacy-first measurement"
Usually means: a label for consent settings, server-side tagging or modelled conversions, not a measurement method in itself.
Ask: which data stops reaching us when a visitor declines consent?
FAQ
Are third-party cookies gone in Chrome?
No. In April 2025 Google said Chrome would keep its current approach to offering users third-party cookie choice, and would not roll out a new standalone prompt1.
Do I need Privacy Sandbox to run ads?
Not as a rule. What your setup needs is a consented, first-party foundation for measurement. Whether any API is part of it is a question for your tracking plan.
Let’s find what’s actually working.
Next step. Check how much of your reported return rests on tracking that may not hold. Use the Is your ROAS real? calculator.