Number Base Converter
Converters
Loading tool...
About This Tool
Free, private, serverless number base converter. Convert between binary, octal, decimal, hexadecimal, and custom bases (2-36) instantly. Supports bulk conversion, shows bit and byte counts. 100% client-side — no data leaves your browser.
How to Use
- Enter a number in the input field.
- Select the input base (binary, octal, decimal, hex, or custom).
- Click Convert to see the number in all bases simultaneously.
- Use the custom base output to convert to any base from 2 to 36.
- Expand Bulk Conversion for multiple numbers at once.
Frequently Asked Questions
What bases are supported?
Any base from 2 to 36. The four most common (binary, octal, decimal, hexadecimal) are shown by default, plus a custom base output field.
How does bulk conversion work?
Enter multiple numbers (one per line) in the bulk input area, select the target base, and click Bulk Convert. All numbers are converted using the same input base selected above.
What is the maximum number size?
The tool uses JavaScript native integers, which safely handle numbers up to 2^53 - 1 (9,007,199,254,740,991). For larger numbers, precision may be lost.
What do Bits and Bytes mean?
Bits shows the minimum number of binary digits needed to represent the number. Bytes shows how many 8-bit bytes are needed (bits rounded up to the nearest multiple of 8).
Guides & Tutorials
In-depth guides for every tool. Learn how to process your data privately, for free, right in your browser.
Read more