Generate Random Bytes
Create a sequence of random binary octets. Runs entirely in your browser, so your data never leaves your device.
Output
The result appears here as you type.
How to use Generate Random Bytes
- 1. Set How many bytes. Skip the input pane; this tool generates from settings alone. Choose How many bytes you need, from a couple of octets for a header stub to hundreds for a payload mock.
- 2. Choose the Format. Format offers Hexadecimal (00-ff) for compact dumps, Decimal (0-255) when a spreadsheet or config expects plain integers, and Binary (8 bits) when you want to see every individual bit.
- 3. Adjust the Separator and copy. Set the Separator to a comma, space or newline to match your target file, then copy the batch from the output pane. Regenerate as often as you like for fresh octets.
When to use Generate Random Bytes
Generate Random Bytes produces arbitrary octets in the notation you actually need, hex, decimal or raw bits, with a separator you control. Random bytes are everyday material for developers: placeholder MAC-like values, dummy packet payloads, seed data for hash experiments. Generating them here beats piping /dev/urandom through three formatting commands.
- Stubbing a binary protocol payload. Your packet parser test needs a 64-byte body it should pass through untouched. Generate 64 hex bytes with comma separators and paste them into the fixture array literal.
- Filling a byte array in source code. A C or Rust example needs an initialized buffer. Decimal format with comma separators produces text you can drop between the braces of the array initializer without editing.
- Practicing hex-to-binary reading. Generate the same byte count twice, once in Hexadecimal and once in Binary (8 bits) format, and quiz yourself on converting between the two notations before a systems exam.
- Creating opaque test identifiers. A staging database wants realistic-looking opaque tokens. Sixteen random hex bytes joined without separators gives you unique-looking identifiers that carry no real user information.
Examples
Sixteen random bytes in hex
Output
a3, 1f, c0, 7e, ...
Bytes as decimal numbers
Output
163, 31, 192, 126
About the Generate Random Bytes tool
Generate Random Bytes is a free online tool that works entirely inside your web browser. Create a sequence of random binary octets. Because the processing happens on your own device, nothing you enter is uploaded, logged or stored anywhere.
This page is one of 112 Binary utilities on EditSafely. Each one does a single job well, and all of them follow the same rule: your input stays on your machine.
You can shape the output with 3 settings, including How many bytes, Format and Separator, and the result refreshes the moment you change one. 2 worked examples further down the page show exactly what the tool produces for real inputs.
Because nothing leaves your device, the tool is suitable for sensitive content such as internal documents, credentials or customer data. It also responds instantly, since every keystroke is handled on your own machine rather than by a remote API.
Frequently asked questions
Does Generate Random Bytes cost anything?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Does the generator send anything to a server?
No data leaves your device. The whole tool is JavaScript that runs inside your browser tab, so there is no upload, no server-side processing and no log of what you did. If you disconnect from the internet after the page loads, it keeps working.
How do I get a different result?
Run the generator again. Each run is computed fresh on your device, and any options you change are applied to the next result immediately.
Do I need to sign up or install anything?
Nothing to install and no account needed. Open the page in any up-to-date browser, including on a phone or tablet, and the tool is ready.
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.