Binary-to-Text

Convert Binary to Decimal, Hex and Octal

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To convert binary to decimal, you add up the place values wherever the binary number has a 1. Binary 1101 has a 1 in the eight, four, and one positions, so it is 8 plus 4 plus 1, which is 13. The same binary string can also be written as hexadecimal or octal, and each is just a different, shorter way of showing the same value. This guide shows how to convert binary to decimal, hex, and octal, with the rule behind each and a free tool for the job.

In this guide

The place-value rule

Binary has two digits, 0 and 1, and each position is worth twice the one to its right: 1, 2, 4, 8, 16, and so on. Reading a binary number means adding the position values wherever a 1 sits. That single rule is the basis of every conversion here, and it is covered in more depth in our guide to number systems.

Decimal, hexadecimal, and octal are simply three different groupings of those same bits. Decimal is the everyday base-10 form, hex groups the bits in fours, and octal groups them in threes. Nothing about the underlying value changes between them.

Convert binary to decimal

Decimal is the base-10 system people count in, so converting binary to decimal turns a machine value into a number you can read at a glance. You add the place values for every 1 in the string, exactly as in the rule above.

For a short number this is quick, but for a long byte or a 16-bit value it is slow and easy to miscount, so the binary to decimal converter does it instantly. Paste the binary and it returns the decimal number.

Convert binary to hexadecimal

Hexadecimal uses sixteen digits, 0 to 9 then A to F, and its key feature is that one hex digit is exactly four bits. That makes hex the compact, readable form of binary used for colour codes, memory addresses, and raw byte data.

To convert by hand you split the binary into groups of four bits from the right and write each group as its hex digit. The binary to hex converter handles the grouping and lookup for you, which removes the most common mistake, splitting the bits in the wrong place.

Convert binary to octal

Octal uses eight digits, 0 to 7, and one octal digit is exactly three bits. It is the older shorthand still seen in Unix and Linux file permissions, where a value like 755 is octal. The binary to octal converter groups the bits in threes and returns the octal value.

One number, three formats

Take the byte 11010110. As decimal it is 214. Grouped into fours, 1101 and 0110, it is D6 in hex. Grouped into threes from the right, 11 010 110, it is 326 in octal. Three different notations, one identical value. Run any of them through the matching converter and you get the same result, because the conversion only changes how the value is written, never the value itself.

Free converters used in this guide

Why these conversions matter

Programmers meet all of these systems daily. A memory address is read in hex, a file permission is set in octal, and a calculated result is checked in decimal. Being able to move a value between them, or letting a converter do it, is part of routine debugging and low-level work. It is also the first thing most computer science courses teach, because it explains how a machine that only knows 0 and 1 can store any number at all.

Frequently asked questions

How do I convert binary to decimal?

Add the place values for every 1 in the binary string, where the positions from the right are worth 1, 2, 4, 8, and so on. A binary to decimal converter adds them up for you.

What is binary 1101 in decimal?

Binary 1101 is 8 plus 4 plus 1, which is 13 in decimal.

Why is hexadecimal grouped in fours?

Because one hexadecimal digit represents exactly four bits, so any group of four binary digits maps cleanly to a single hex digit.

Is converting binary to decimal reversible?

Yes. The value is identical in every base, so the conversion is lossless and the same number can be written back in binary without any change.

What is octal still used for?

Most commonly Unix and Linux file permissions, where a setting such as 755 is an octal number. One octal digit equals three bits.

Convert Binary to Text and Text to Binary

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To convert binary to text, you turn each group of eight bits back into the character it stands for. Computers store every letter and symbol as a number, and that number is held in binary, so a string like 01001000 01101001 is really just the word Hi written the way a machine keeps it. This guide shows how to convert binary to text and text to binary, explains the simple rule that connects the two, and points you to a tool for each direction.

In this guide

How text and binary connect

Every character has a number assigned to it by a standard called ASCII. The capital letter A is 65, lowercase a is 97, the digit 0 is 48, and a space is 32. A computer then stores that number in binary, using eight bits, which is one byte, for each character.

So converting between text and binary is really two steps joined together: character to number to binary, or binary to number to character. The numbers are the bridge, and they come from the same ASCII table covered in our guide to number systems. Once you see that text is just numbers in disguise, both conversions make sense.

Convert binary to text

To read binary as text, you split the string into groups of eight bits, turn each group into its decimal number, and look up the character that number represents. The group 01001000 is 72, which is the letter H.

Doing that by hand for a whole message is slow and easy to slip on, so the binary to text converter does it in one step. Paste the binary, and it returns the readable text. For binary that uses extended characters, the binary to UTF-8 decoder handles the wider character set, and the binary to ASCII converter is another route to the same result.

Convert text to binary

The reverse works the same way backwards: take each character, find its number, and write that number in eight bits. The letter H is 72, which in binary is 01001000.

The text to binary converter turns any text into its binary codes instantly, and the ASCII to binary converter does the same job. You type or paste the text, and you get back a binary string, one byte per character.

ASCII and UTF-8

Plain ASCII covers the basic English letters, digits, and common symbols, and each fits in a single byte. That is why a simple message converts cleanly to eight bits per character.

Modern text often goes beyond that, with accented letters, other alphabets, and emoji. These use a standard called UTF-8, which lets a single character take more than one byte when it needs to. If your binary represents anything beyond basic English, the UTF-8 decoder is the tool that reads it correctly, because a plain ASCII reading would only get the simplest characters right.

A worked example

Take the word Hi. The letter H is 72, which is 01001000 in binary. The letter i is 105, which is 01101001. Put them together and Hi becomes 01001000 01101001. Run that binary back through the binary to text converter and you get Hi again. The conversion is lossless, so nothing is added or removed in either direction.

Free converters used in this guide

Where this is used

Converting between binary and text comes up in learning and teaching how computers represent data, in puzzles and capture-the-flag challenges where a message is hidden as binary, and in debugging, where seeing the raw bits of a string helps explain an unexpected result. It is also a quick way to understand why a file that looks like gibberish is really just text the program read with the wrong rules.

Frequently asked questions

How do I convert binary to text?

Split the binary into groups of eight bits, turn each group into its number, and look up the matching character. A binary to text converter does all three steps for you at once.

How many bits is one character?

One basic ASCII character is eight bits, which is one byte. Characters beyond basic English use UTF-8 and can take more than one byte.

What is the binary for the letter A?

The capital letter A is the number 65, which in eight-bit binary is 01000001.

Is converting binary to text reversible?

Yes. The conversion is lossless, so text converted to binary and back returns exactly the original text.

Why does my binary not convert correctly?

Usually the bits are not grouped into clean bytes of eight, or the text uses characters beyond basic ASCII. For the second case, use a UTF-8 decoder rather than a plain ASCII reading.