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Binary Base Converter

Encode/Decode

Binary (Base 2)

Octal (Base 8)

Decimal (Base 10)

Hexadecimal (Base 16)

About This Tool

🔢 Binary Base Converter – Instant Numeral System Translation

The Binary Base Converter is an all-in-one numeral-system translation tool for developers, students, and engineers. Enter any number in binary, octal, decimal, or hexadecimal, and the tool instantly shows the equivalent in every other base — no manual calculation required.

🧮 How Base Conversion Works

Every numeral system expresses quantity using a different radix (base). The four most common bases in computing are:

BaseNameDigits UsedExample (202₁₀)
2Binary0, 111001010
8Octal0–7312
10Decimal0–9202
16Hexadecimal0–9, A–FCA

Conversion always routes through decimal as an intermediate: a binary string is first parsed into its decimal value, then re-expressed in each target base using the division-remainder algorithm (for integers) or the repeated-multiplication algorithm (for fractional parts). The tool uses JavaScript's BigInt API to guarantee full precision for integers of any size, not just those within 32-bit or 53-bit limits.

🔑 Key Features

⚡ Live Bidirectional Conversion

Any of the four base input fields is editable. Typing in one field immediately updates all others — no button click needed.

📏 Bit-Width Padding

Choose 4, 8, 16, 32, or 64 bits to zero-pad the binary output to a fixed width. This mirrors the actual register widths used in CPUs (uint8_t, int32_t, etc.) and makes comparing values in different representations straightforward.

± Signed Two's Complement

Enable signed mode (requires a bit width) to interpret binary values as Two's Complement signed integers. For example, the 8-bit value 11111110 becomes −2 in decimal.

🔢 Custom Base (2–36)

Convert to any arbitrary base from 2 to 36 using the standard digit set (0–9 then A–Z). Useful for base-5, base-12, base-32, or any domain-specific encoding.

🔣 Fractional / Floating-Point Support

Enter a decimal like 10.625 and the tool converts the integer and fractional parts separately. For example, 10.625₁₀ equals 1010.101₂ and A.A₁₆.

🎛 Interactive Bit Grid

A clickable bit grid shows each bit position. Clicking any bit toggles it between 0 and 1, instantly propagating the change to all base representations — ideal for hands-on learning about bit manipulation.

📋 Step-by-Step Breakdown

Expand the Steps panel to see the full division-remainder walkthrough for any target base. Each row shows the dividend, quotient, and remainder, with the final result read from bottom to top.

🧩 Two's Complement Explained

Modern processors use Two's Complement to store negative integers because it simplifies hardware arithmetic — addition and subtraction use the same circuit. For an n-bit signed integer, the most-significant bit (MSB) acts as the sign bit. If the MSB is 1, the value is negative and equals the unsigned interpretation minus 2n. For an 8-bit number: 1111 1110₂ unsigned = 254, signed = 254 − 256 = −2.

💡 Nibble and Byte Grouping

Binary strings become hard to read at 16+ bits. The Grouping toggle inserts spaces every 4 bits in binary output (nibbles) and every 2 hex digits (bytes), matching the notation used in datasheets and assembly listings:

Without grouping:  0001101000111111
With nibbles:      0001 1010 0011 1111
Hex bytes:         1A 3F

🛠 Typical Use Cases

  • Embedded / hardware development — verify register values in binary and hex while matching datasheet bit-field positions.
  • Networking & IP addressing — convert subnet masks, IPv4 octets, and MAC address bytes between decimal and hex.
  • Cryptography & security — inspect hash digests, key material, and byte sequences across representations.
  • Computer science education — demonstrate how the same quantity looks in different bases and how Two's Complement encodes negative numbers.
  • Color codes — RGB values like #1A3F are directly readable in the hexadecimal field.

Frequently Asked Questions

Is the Binary Base Converter free?

Yes, Binary Base Converter is totally free :)

Can I use the Binary Base Converter offline?

Yes, you can install the webapp as PWA.

Is it safe to use Binary Base Converter?

Yes, any data related to Binary Base Converter only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does the Binary Base Converter work?

Enter a number in any of the four base fields (binary, octal, decimal, or hexadecimal) and the tool instantly converts it to all other bases using JavaScript's BigInt API for full precision. Editing any field triggers live recalculation of all other fields.

What is Two's Complement signed mode?

Two's Complement is the standard way computers represent negative integers. When signed mode is enabled with a chosen bit width (e.g., 8-bit), a binary value whose most-significant bit is 1 is interpreted as a negative number. For example, 11111110 in 8-bit signed mode equals -2 in decimal.

What does the bit-width selector do?

Selecting a bit width (4, 8, 16, 32, or 64) zero-pads the binary output to that exact length, which is useful for verifying values in CPU registers, memory addresses, or data types like uint8, int16, etc. It also powers the interactive bit-flip grid.

How do I convert to a custom base like base-5 or base-36?

Enter your decimal (or any base) number in the main fields, then type a base number between 2 and 36 in the Custom Base field. The tool uses digits 0–9 followed by letters A–Z for bases above 10, which is the standard convention for positional notation.

How accurate is the conversion for very large numbers?

The tool uses JavaScript's BigInt for all integer conversions, so there is no precision loss up to arbitrarily large integers. For numbers beyond 64-bit unsigned range, a warning is displayed but conversion still proceeds correctly.

Can I convert fractions or floating-point numbers?

Yes. Enter a decimal number with a fractional part (e.g., 10.625) in the decimal field. The tool converts the integer and fractional parts separately: the integer part via standard base conversion and the fractional part via the repeated-multiplication algorithm.