Binary Converter
A front panel for numbers and text: lamps show the bits, switches set them. Convert text to binary and back, and any number between decimal, hex, octal and binary.
Status
Address · number
Data · text to binary
Data · binary to text
Text to binary, and every base between
Computers store text as numbers and numbers as bits. This panel shows both at once: type a word and each character becomes a row of eight lamps, its byte in binary, with the same value in decimal, hex and octal beside it. Type a number in the address row and the lamps show its bits; flip a switch and the readouts follow. Paste binary, hex or decimal bytes at the bottom to turn them back into text.
How text becomes bits
Plain English letters are ASCII: one byte each, so H is 72, 0x48, 01001000. Everything else, from accented letters to emoji, is UTF-8 and takes two to four bytes, which the panel shows as one lamp row per byte with a dot marking the continuation rows. The UTF-8 status lamp lights whenever the text contains one of those characters.
Why a front panel
Before keyboards and screens, machines like the Altair 8800 and the IMSAI 8080 showed their memory as rows of lamps and took input from rows of toggle switches: up meant 1, down meant 0, and the lamps were grouped in threes because operators read them in octal. This page keeps that convention. Every lamp here is also a switch.
How do I convert binary to text?
Paste the bytes into the bottom box: binary in groups of eight (spaces optional), hex pairs (with or without 0x), or decimal numbers 0 to 255 separated by spaces or commas. Auto works out which one you pasted; pick a base by hand if it guesses wrong.
Can I convert a negative number?
Yes. Type -1 and the address row shows its two's complement at the chosen width: all lamps lit for 16 bits, which is 0xFFFF. The DEC readout shows the unsigned value the lamps represent.
What does OVF mean?
Overflow: the number you typed needs more bits than the current width. Only the low bits are shown; switch to 32 bits to see all of them.
Is anything uploaded?
No. The whole panel runs in your browser; nothing you type leaves the page.