# What is a favicon?
> A favicon is the small icon a website shows in tabs and bookmarks — /favicon.ico or a link rel=icon. Sizes, formats, and how Square Town fetches yours for the wall.
Source: https://square.pov.town/glossary/favicon
A **favicon** ("favourite icon") is the small square image a website provides so browsers can show it in tabs, bookmarks, history and home screens. Browsers look for `/favicon.ico` at the site root by default, or for one or more `` tags in the page's ``. On Square Town ([square.pov.town](/)) the favicon is the whole product: you give a URL, Square Town fetches the icon, and that icon becomes your 1×1 square on the wall.
> **TL;DR:** ship a 32×32 PNG (or an SVG) and declare it with ``. If your site has none, Square Town shows a clown instead.
## What it is technically
- **Default location:** `https://yourdomain/favicon.ico` — an ICO file, which can bundle several sizes in one file.
- **Declared icons:** ``; you may list several sizes.
- **Common sizes:** 16×16 and 32×32 for tabs and bookmarks, 180×180 for `apple-touch-icon` (iOS home screen), 192×192 (and 512×512) for Android and PWA manifests.
- **SVG:** `` scales to any size and is supported by modern browsers; keep an ICO or PNG fallback.
Design rules for something that must read at 16 pixels are their own topic: [/blog/favicon-design-tips-16px](/blog/favicon-design-tips-16px). Adding one step by step: [/blog/how-to-add-a-favicon](/blog/how-to-add-a-favicon).
## How Square Town fetches it
Square Town does not crawl your site itself. It asks Google's favicon service — `https://www.google.com/s2/favicons?domain=yourdomain&sz=…` — which already resolves `/favicon.ico`, `` and the rest, and caches the result. The wall loads icons through Square Town's own proxy at `/favicon/:domain` (sizes 16–256), which adds the CORS header WebGL textures need and caches at the edge for a day. Right after purchase Square Town checks the same service: a 404 means no favicon, and the square joins the [Hall of Clowns](/glossary/hall-of-clowns) until you add one and press "I fixed my favicon". The icon's dominant colour is also sampled in the browser to tint your [click tower](/glossary/click-tower) in 3D.
## Why it matters
A favicon is designed to be legible at 16×16, which is why a [favicon wall](/glossary/favicon-wall) can sell 1×1 cells: your existing icon reads where a 10×10 [pixel ad](/glossary/pixel-advertising) never did. It also removes design work — no upload, no logo file, one square per domain. Elsewhere in the landscape, favicons appear as the unit only in crawled or curated projects (Nmap's Icons of the Web, StartupBar, favicon.im); logo walls make you upload instead. Argument in full: [/blog/why-favicons-beat-pixels](/blog/why-favicons-beat-pixels).
## Example
Your site serves `/favicon.ico` with 16×16 and 32×32 layers and declares a 180×180 apple-touch-icon. You paste the URL into Square Town, Google's service returns the icon, and your square shows it within seconds — in colour, in 2D and on top of a tower in 3D.
## FAQ
### What size favicon does Square Town use?
Whatever your site serves; Square Town requests it from Google's favicon service at 16–256 px depending on zoom. A crisp 32×32 PNG or an SVG works best.
### My site has a favicon but Square Town shows a clown — why?
Google's favicon service hadn't picked it up yet, or it's declared in a way it can't find. Check that `/favicon.ico` or a `` resolves publicly, then press "I fixed my favicon".
### Can I upload a different image to Square Town?
No. Square Town only shows the favicon your domain actually serves.
### Do I need an ICO file in 2026?
Not strictly — a PNG or SVG declared with `` is fine — but a `/favicon.ico` fallback is still the safest way to be found by every crawler and service.