Guide: Number Base Converter
↑ Back to toolWhat is this tool?
This number base converter (also called a radix converter) converts whole numbers between binary, octal, decimal, hexadecimal, and any base from 2 to 36. You type a number, choose which base it is written in, and the tool shows the same value in the output bases you select (e.g. binary, ternary, octal, decimal, hex, base 32, base 36). Large integers use JavaScript BigInt so long hex or binary strings do not lose precision. All conversion runs in your browser—no sign-up.
Digits are 0–9 and a–z for bases above 10 (case-insensitive input). This is the standard way to represent values in hex to decimal, binary to decimal, and octal converter workflows.
💡 Quick tip
Set source base to match how you typed the number (e.g. base 16 for ff, base 10 for 255). Toggle which output bases appear so you only copy what you need.
Why use a base converter?
Developers use a binary to decimal or hex to decimal converter when reading memory addresses, color codes, permissions bitmasks, or protocol fields. A single tool that handles any radix 2–36 avoids mental math and spreadsheet errors. BigInt support matters for cryptographic constants, large flags, or 64-bit-style values expressed in hex.
- Debug embedded systems and bitwise operations
- Convert web colors (#RRGGBB) and similar hex literals to decimal
- Teach or verify number-system homework without a calculator
Bases supported
Input: You choose the source radix from quick chips (2, 3, 4, 5, 8, 10, 12, 16, 32, 36) or enter any base from 2 to 36.
Output: The tool can show conversions to binary (2), ternary (3), quaternary (4), octal (8), decimal (10), duodecimal (12), hexadecimal (16), base 32, and base 36—toggle which columns are visible and copy each value independently.
Key features
- Radix 2–36 — Standard digit set; bases above 10 use letters a–z.
- BigInt precision — Large integers without floating-point rounding.
- Multiple outputs — Show or hide binary, octal, decimal, hex, and other bases.
- Copy per base — Copy any converted value to the clipboard.
- Client-side — Your numbers are not sent to a server.
How to use
- Enter the number — Type digits (and letters for bases > 10) in the input field.
- Set the source base — Select the radix your input uses (e.g. 16 for hex).
- Choose outputs — Toggle which target bases appear in the list.
- Copy — Use the copy button next to any row to copy that representation.
Use cases
| Scenario | How this tool helps |
|---|---|
| Web / CSS colors | Convert hex color components to decimal for scripts or design tokens. |
| Low-level programming | Move between binary masks and decimal or hex in documentation. |
| Base 36 IDs | Encode or decode compact alphanumeric representations with the base 36 output. |
| Learning | Verify manual conversions for computer science courses. |
Best practices
- Match base to input — Wrong source base produces wrong outputs; double-check radix before copying.
- Integers only — This tool is for whole numbers; fractional values are not supported.
Common mistakes
- Hex without setting base 16 — If you paste
ffbut leave source as decimal, the result is invalid or wrong. - Invalid digits — Digits must be valid for the chosen base (e.g. no
8in octal).
FAQ
What is a number base converter?
A tool that expresses the same integer in different radices—binary (base 2), decimal (10), hexadecimal (16), and so on. This converter supports bases 2 through 36.
Binary to decimal and hex to decimal?
Yes. Enter your number, set the source base to 2 for binary or 16 for hex, and read the decimal (and other) outputs in the table.
Why BigInt?
JavaScript numbers are limited for very large integers. BigInt keeps conversions exact for long bit patterns and large hex strings.
Is my number sent to a server?
No. Conversion runs entirely in your browser.
Related terms
This tool is commonly searched as number base converter, radix converter, binary to decimal, hex to decimal, decimal to binary, decimal to hex, octal converter, base 36, base converter online, and convert number base. It helps you translate between numeral systems for development and study.
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Conclusion
This number base converter converts integers between binary, hex, decimal, octal, and other radices up to 36 with BigInt precision. For text-as-bytes encoding, see Hex or Binary tools; for unified encode/decode, try Encoder/Decoder.