🔄 Number Base Converter

What is Number Base Converter?

The Number Base Converter reads a number in any base from 2 to 36 and instantly rewrites it in binary, octal, decimal, hexadecimal and any custom base you choose. Type a value, pick its source base and a custom target base, and the tool validates every digit before converting with exact BigInt arithmetic — so even numbers far past the safe-integer range come out correct. Each converted row has its own copy button. Everything is computed locally in your browser with no account and no data upload.

How to Use Number Base Converter

1. Type the value you want to convert in its source base
2. Choose the source base and the custom base you want as the extra row
3. Read the binary, octal, decimal, hex and custom-base results and copy any of them

Why Use Our Number Base Converter?

• Instant conversion into binary, octal, decimal and hexadecimal plus a custom base from 2 to 36
• Every digit validated against the source base with clear error messages
• Exact BigInt arithmetic that handles values far beyond the safe-integer range
• Per-row copy buttons so you can grab any representation in one click

Common Use Cases

• Reading a binary or hex memory dump as a decimal value
• Preparing a base-36 short code or ID from a decimal number
• Checking a number written in an unfamiliar base like octal or base 32

Frequently Asked Questions

• Why are binary and hexadecimal bases so common?▾
  Binary is the native number system of computers — every bit is a 0 or 1 — while hexadecimal packs four bits into one character, which is why it is used for memory addresses, color codes and machine output.
• How large a value can this converter handle?▾
  Arbitrarily large positive and negative whole numbers. Conversion runs on BigInt, so results stay exact even past 9 quadrillion, where a note reminds you the value exceeds the safe-integer range.
• What is base 36?▾
  Base 36 uses the digits 0–9 followed by the letters A–Z as single symbols, so 35 is one digit (Z) and 36 rolls over to 10. It is a compact way to write big numbers as short strings.