Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal live as you type, plus any custom base from 2 to 36. Everything is calculated locally in your browser.
Convert number base online for less common bases, such as base 7 or base 36, not just the four common ones above.
About Number Base Converter
This number base converter free tool converts between binary, octal, decimal, and hexadecimal in real time. Instead of converting one pair at a time, all four fields stay in sync, so typing a hexadecimal color code or a binary flag value instantly reveals its decimal, octal, and binary or hex equivalents.
Developers working with memory addresses, bitwise flags, color values, or low-level protocols often need to convert number base online quickly. This binary hex octal converter also includes an advanced mode for any base from 2 to 36, covering less common systems like base 7 or base 36 used in short URL encoding.
| Binary | Octal | Decimal | Hex |
|---|---|---|---|
| 11111111 | 377 | 255 | FF |
| 1010 | 12 | 10 | A |
| 1000 | 10 | 8 | 8 |
| 10000000000 | 2000 | 1024 | 400 |
How to Use
- Type a value into the Binary, Octal, Decimal, or Hexadecimal field.
- Watch the other three fields update automatically with the converted value.
- If a field shows an error, remove any characters that are not valid digits for that base.
- For less common bases, open the Advanced section, choose a base from 2 to 36, and enter a value to see its decimal equivalent.
Why Use This Converter
Live, Linked Fields
This binary to decimal converter updates every other base the moment you type, without needing a separate convert button.
Instant Validation
Invalid digits for a given base are flagged immediately with a clear error message, instead of silently producing a wrong result.
Custom Base Support
Beyond the common four bases, convert to and from any base between 2 and 36 using the Advanced section.
Zero Server Contact
Every conversion runs locally with client-side JavaScript, so the values you type are never sent anywhere.
Who Should Use This Tool
- Software engineers debugging bitwise flags, memory addresses, or binary protocol data.
- Web developers using a hex to decimal converter online to translate color codes or CSS values.
- Computer science students learning how binary, octal, and hexadecimal number systems relate to decimal.
- Embedded and network engineers who regularly convert number base online while inspecting registers or packet data.
Privacy first. No number you type into this tool is ever uploaded, logged, or stored on a server. Every conversion happens locally on your device.