# Why cookieless by default

> Useful analytics without a consent banner in the default mode, and an honest opt-in when you need more.

Canonical: https://atrby.site/blog/cookieless
Last updated: 2026-10-16

## Why there's no banner

Most sites add a cookie banner because their analytics stores an identifier in the visitor's browser. atrby doesn't, by default.

## How visitors are counted

When a page loads, our server combines a random salt, your site, and the visitor's network address and browser into a one-way hash. The salt changes every day and the old one is deleted, so yesterday's ids can't be recreated and nobody, including us, can follow a person across days.

## What you give up

A person who visits on Monday and again on Thursday counts as two visitors. For revenue, that gap is closed differently: pass `atrby.ids()` into checkout and call `atrby.identify()` at sign-up, and the payment is matched to the visit that started it.

## When cookie mode makes sense

Long sales cycles where you need to follow anonymous visitors over weeks. Switch the site to cookie mode in settings and show a consent banner in the EU and UK first.

## Related
- [How to calculate ROAS per campaign from Stripe payments](https://atrby.site/blog/roas-per-campaign-stripe)
- [Import Google Ads spend into your analytics, step by step](https://atrby.site/blog/import-google-ads-spend)
- [Meta Ads in another currency: converting spend for ROAS](https://atrby.site/blog/meta-ads-currency-roas)