Free Number Base Converters
Convert numbers between binary, hexadecimal, octal, decimal, and Roman numerals instantly. Essential tools for programming, computer science, and mathematics.
Binary to Decimal Converter
Enter a binary number (base 2) to convert it to its decimal (base 10) equivalent. Essential for computer science, digital electronics, and networking.
Use tool →Decimal to Binary Converter
Enter a decimal number to get its binary representation. Understand how computers store numbers and learn binary arithmetic.
Use tool →Hex to Decimal Converter
Enter a hexadecimal number to convert it to decimal. Widely used for color codes, memory addresses, and data representation in programming.
Use tool →Decimal to Hex Converter
Enter a decimal number to get its hexadecimal equivalent. Useful for generating color codes, debugging, and working with low-level data formats.
Use tool →Octal to Decimal Converter
Enter an octal number to convert it to decimal. Octal is used in Unix file permissions, legacy computing, and digital systems.
Use tool →Decimal to Octal Converter
Enter a decimal number to get its octal representation. Commonly needed for setting Unix file permissions and understanding base-8 arithmetic.
Use tool →Binary to Hex Converter
Enter a binary number to convert it to hexadecimal. Each group of 4 binary digits maps directly to one hex digit, making this conversion natural.
Use tool →Hex to Binary Converter
Enter a hexadecimal number to see its full binary expansion. Each hex digit expands to exactly 4 binary bits for clear bit-level analysis.
Use tool →Binary to Octal Converter
Enter a binary number to convert it to octal. Groups of 3 binary digits map to one octal digit, making this a straightforward conversion.
Use tool →Octal to Binary Converter
Enter an octal number to see its binary equivalent. Each octal digit expands to exactly 3 binary bits for detailed bit-level representation.
Use tool →Hex to Octal Converter
Enter a hexadecimal number to convert it to octal. The tool converts through binary internally for accuracy — useful for number base exercises.
Use tool →Octal to Hex Converter
Enter an octal number to get its hexadecimal equivalent. Converts via binary internally for precise results across any input size.
Use tool →Decimal to Roman Converter
Enter any number from 1 to 3,999 to see its Roman numeral equivalent. Used for clock faces, movie credits, outlines, and historical dates.
Use tool →Roman to Decimal Converter
Enter a Roman numeral to convert it to a decimal number. Validates the input and handles subtractive notation like IV (4) and IX (9) correctly.
Use tool →Learn More
Read our comprehensive guide to get the most out of these tools.
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