# What is a residential proxy? > A residential proxy sends your traffic out through an address an ISP assigned to a home connection, so sites see a household rather than a data center. Source: https://mosaicbrowser.com/glossary/residential-proxy ## Residential proxy: an exit on a home internet connection A residential proxy is a proxy whose exit address belongs to a consumer internet connection assigned by an ISP, so websites see traffic arriving from a household rather than from a hosting company's data center. ![Residential proxy, drawn as a mosaic of tiles](https://mosaicbrowser.com/covers/residential-proxy.webp) Every request a browser makes carries an IP address, and that address says who owns it. Addresses belong either to internet providers that hand them to homes and phones, or to hosting companies that rent them to servers. A residential proxy routes your browser's traffic through an address of the first kind, and that address becomes part of what a site reads alongside the [browser fingerprint](https://mosaicbrowser.com/glossary/browser-fingerprint). Mosaic is a desktop app Email yourself the link and open it on your computer. [How it works: Provider minting](https://mosaicbrowser.com/features/proxy-providers) ## How it works You connect to the proxy seller's gateway, a host and port, with a username and password. The seller forwards your traffic out through one address in a pool of residential connections. Options such as the country, sometimes the city, and a session id are usually written into the username. Each seller spells them differently. A **rotating** setup gives you a different exit per connection or every few minutes. A **sticky** session keeps the same exit for a set time, which is what a logged-in account needs, since an account that changes address every few minutes looks odd. ## Why it matters for accounts A site looks at the exit address before anything else. A geo lookup tells it the address's country and whether the network is an ISP or a hosting company, and reverse DNS often names the hosting company outright. A shopper whose traffic arrives from a server rack is unusual; one arriving from a home broadband connection is not. Residential exits also carry history. Addresses in a pool are reused, and one may already be on a spam blocklist. [How to check a proxy before you use it](https://mosaicbrowser.com/guides/how-to-check-a-proxy-before-you-use-it) covers blocklists, residential checks and leaks. ## How Mosaic uses them In Mosaic, a proxy seller's gateway line is saved once as a [provider](https://mosaicbrowser.com/features/proxy-providers), and every profile mints its own sticky session from it, so each profile has its own exit. Mosaic checks the proxy before every launch, measures the exit's location, and sets the profile's timezone and language from it. A session that dies is replaced with a new one instead of being retried. ## Questions ### Residential or data center proxy? Data center proxies are fast and cheap, and fine for work that does not involve consumer accounts. For logged-in accounts on consumer platforms, a residential exit looks like an ordinary customer. ### What is a sticky session? A session id in the proxy login that keeps you on the same exit for a period. A new session id usually means a new exit address. ### Can two profiles share a residential proxy? They can share a gateway, but not a session. Two profiles on one session share one exit address, which links them. Mosaic mints a separate session for each profile. ## Related [How to check a proxy before you use it](https://mosaicbrowser.com/guides/how-to-check-a-proxy-before-you-use-it): Check that a proxy answers and tunnels, where its exit really is, whether the address is residential or blocklisted, and that the browser stays behind it. [Provider accounts: one gateway line, one exit per profile](https://mosaicbrowser.com/features/proxy-providers): Paste your proxy seller's gateway line once and Mosaic mints a separate session for every profile, so each one browses from its own exit address. [How to manage multiple accounts without getting them linked](https://mosaicbrowser.com/guides/how-to-manage-multiple-accounts-without-getting-linked): Accounts get linked by shared cookies, IPs, fingerprints and habits. Give each its own profile, exit and history, then test it before you trust it. [Browser fingerprint: what a site can read about your machine](https://mosaicbrowser.com/glossary/browser-fingerprint): A browser fingerprint is the set of values a site reads about your browser and computer, which together recognize you without cookies. What goes into one. [Mosaic for e-commerce sellers running several stores](https://mosaicbrowser.com/use-cases/e-commerce-sellers): Keep each store you are entitled to run in its own browser profile, with its own exit, cookies, logins and downloads, so stores never mix.    ## See residential proxy on a real profile Mosaic shows the values a site reads, per profile, and runs a leak test from inside the profile’s own page. Free holds 3 profiles. Pro is $49 a month for any number. Mosaic is a desktop app Email yourself the link and open it on your computer.