Duplicate Hex Digits
Create multiple copies of every digit in a hex number. Runs entirely in your browser, so your data never leaves your device.
0 chars · 0 lines
Output
The result appears here as you type.
How to use Duplicate Hex Digits
- 1. Paste the hex to expand. Put a hex string such as a1f into the input pane. The tool walks through it digit by digit, so anything from a short color code to a long hash works as input.
- 2. Pick how many Copies. Copies sets how many times each digit repeats. Two turns a1f into aa11ff, the classic way to expand a 3-digit CSS color into 6 digits. Higher counts stretch values for visual padding or test strings.
- 3. Set a Separator for lists. When the input contains multiple values split by a space or comma, enter that character as the Separator. Each value gets its digits duplicated independently instead of the whole line being treated as one number.
- 4. Copy the widened result. Take the expanded string from the output pane. Because every digit was repeated in place, the result keeps the original ordering, which matters when you paste it into a stylesheet or fixture.
When to use Duplicate Hex Digits
Duplicate Hex Digits repeats every nybble of a hex string a chosen number of times. Its most practical job is expanding shorthand hex colors, where doubling digits is exactly the rule CSS uses, but it also earns its keep making elongated test values and visually distinctive placeholder data.
- Expanding shorthand CSS colors. A legacy stylesheet is full of 3-digit colors like #a1f, but your design tokens pipeline only accepts 6-digit values. Doubling each digit converts them with the exact semantics browsers apply.
- Stretching values to a fixed field width. A test harness needs 32-character hex strings, but your seed values are 16 digits. Duplicating each digit doubles the length while keeping the string recognizably derived from the seed.
- Making IDs easier to eyeball. When demonstrating a matching bug you want IDs that are obviously distinct at a glance. Tripling digits turns 4f into 444fff, which is much harder to misread across log lines in a terminal.
Examples
Double each digit
Input
a1f
Output
aa11ff
About the Duplicate Hex Digits tool
Duplicate Hex Digits runs as plain JavaScript in your browser tab, with no server behind it. Create multiple copies of every digit in a hex number. Whatever you put in stays on your device from start to finish.
The tool is part of EditSafely's Hex Tools section, 108 single-purpose utilities built around the same idea: open the page, get the result, keep your data to yourself.
You can shape the output with 2 settings, including Copies and Separator, and the result refreshes the moment you change one. A worked example further down the page shows exactly what the tool produces for a real input.
That local-first design has practical benefits beyond privacy. The tool keeps working on a flaky connection once the page has loaded, results are instant because nothing round-trips to a server, and it is safe to use with confidential material.
Frequently asked questions
Is Duplicate Hex Digits free to use?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Is it safe to paste sensitive or confidential data?
Everything happens locally. Your browser downloads the tool's code once, then does all the processing itself; nothing you enter is transmitted, stored or logged. You can even go offline after the page loads and it will still work.
How much text can I process at once?
There is no fixed limit. Because the work happens on your own device rather than on a shared server, the practical ceiling is your machine's memory, which comfortably handles inputs far larger than typical online tools allow.
Do I need to sign up or install anything?
No. The tool works in any modern browser on desktop, tablet or phone. There is no account to create, no extension to add and no software to install.
How do I use the result?
The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.