Binary Converter — Free Online Decimal, Hex & Number Base Converter

Binary Converter — Free Online Decimal, Hex & Number Base Converter. Free online binary converter. Convert numbers between binary, decimal, hex, octal and any base instantly. Decimal to binary, hex to decimal, and more — 100% free.

Convert any number between binary, decimal, hexadecimal, octal, and any base from 2 to 64 instantly with our free binary converter .

Enter a number in any base and get all common representations at once — ideal for computer science students, developers debugging memory addresses, and engineers working with bitwise operations.

Our hex to decimal and decimal to binary conversions are the fastest way to check your arithmetic without leaving the browser.

The bit-length indicator shows exactly how many bits your number needs in its binary form — useful for sizing registers and data types. All calculations run locally — nothing is sent to any server. Why use an online number base converter?

Switching between binary, hex, and decimal is one of the most common tasks in systems programming, electronics, and computer science coursework.

Our hex converter lets you instantly see every representation of a number side by side — binary (base 2), octal (base 8), decimal (base 10), hexadecimal (base 16), and any custom base up to 64.

The decimal to hex direction is essential for color codes, memory addressing, and protocol fields. Need to encode the result as a string? Try our Base64 Encoder for text encoding, or our Base64 File Converter for binary data.

Frequently asked questions

How do I convert decimal to binary or hex?

Enter the number in Input number and keep Input base at 10. The Binary (2), Octal (8), Decimal (10), Hexadecimal (16) and Base64 (64) fields update instantly, along with the bit length; click the copy icon beside any result.

How do I convert hex to decimal?

Set Input base to 16 and type the hex value, for example ff, FF or 0xFF; the Decimal (10) field shows 255. Hex letters can be upper or lower case, and a 0x prefix is accepted when Input base is 16, just as 0b is for base 2 and 0o for base 8.

Can I convert to any number base, not just binary, octal and hex?

Yes. Input base and the custom Base field accept any base from 2 to 64. Digits are 0-9, then a-z for values 10 to 35, then A-Z for 36 to 61, then + and / for 62 and 63. Up to base 36 letters can be typed in either case; above 36 case matters.

Why do I get an Invalid digit error?

Each character must be a valid digit for the chosen Input base, for example only 0 and 1 in base 2; the error names the wrong character and lists the allowed digits. Spaces inside the number, minus signs and decimal points are not accepted. A 0x, 0b or 0o prefix only works with base 16, 2 or 8 respectively.

Is there a size limit on the number?

No practical limit: conversion uses JavaScript BigInt arithmetic, so very large integers such as 64-bit or 128-bit values convert exactly without rounding. Only non-negative whole numbers are supported.

What does Bit length mean?

Bit length is the number of binary digits needed to write the number without leading zeros; for example 42 needs 6 bits (101010). It helps you choose a data type or register size such as 8, 16, 32 or 64 bits.

How to use this online tool

Binary Converter — Free Online Decimal, Hex & Number Base Converter is designed for fast browser workflows when you need to format, validate, convert, decode, encode, generate, or inspect data without opening a heavy desktop app. Start with the input field or visible options, review the result, then copy or download the output for the next step.

Private processing in your browser

Binary Converter — Free Online Decimal, Hex & Number Base Converter keeps the normal processing step local in your browser. That is useful for code snippets, tokens, documents, configuration values, text samples, and other material that should not be sent to a remote service unless you explicitly choose to share it.

When this tool is useful

Use Binary Converter — Free Online Decimal, Hex & Number Base Converter for repeatable developer tasks, technical documentation, QA checks, quick conversions, debugging, content cleanup, and internal team workflows. The page focuses on clear inputs, immediate feedback, and output that is easy to reuse in code, reports, tickets, emails, or notes.

Practical tips

Before copying the final result, check important details such as spacing, casing, filenames, encoding, token structure, line breaks, or output format. Small checks prevent mistakes when the result is reused in source code, API requests, documentation, spreadsheets, or shared files.