Identicon generator
An identicon is a small symmetric picture computed from a string, used as a default avatar. Type a name, e-mail or ID and the pattern appears; the same text always gives the same picture. Choose colours and download PNG or SVG.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Type any text, such as a username or an e-mail address.
- Leave Pick the colour from the text on, or choose your own pattern colour and background.
- Set the margin (0 to 2 cells) and the download size, then save the PNG or SVG.
How it works
The text is hashed with 32-bit FNV-1a. Fifteen of its bits decide whether the cells in the left three columns of a 5 by 5 grid are filled, and columns four and five mirror columns two and one, which gives the symmetric look. The colour hue comes from a second hash of the same text with a fixed salt.
Worked example
The hash of the single letter “a” is 0xe40c292c in FNV-1a. Its lowest bit is 0, so the top-left cell is empty; the grid is built from the next bits in the same way.
Tips
- Normalise the text first (for instance lower-case e-mails) if you want “Ada@x.com” and “ada@x.com” to match.
- A margin of 1 cell keeps the pattern from touching the edge of an avatar circle.
Frequently asked questions
Will the same text always give the same identicon?
Yes. The pattern depends only on the characters you type and on the algorithm, which has no random part. Changing even one character changes the picture.
Is this the same as GitHub's identicons?
It follows the same idea (a 5 by 5 grid, mirrored left to right), but the hash and the colour rule are our own, so the pictures will not match GitHub's for the same text.
Is an identicon a secure way to hide an e-mail address?
No. It is a one-way picture of a short hash, and with only 15 pattern bits many different texts share a pattern. Use it as a visual hint, not as an identifier or as protection.
Why SVG as well as PNG?
The SVG is a single path of squares, so it is tiny and stays sharp at any size. The PNG is the same picture drawn at the size you pick.