A programmer's calculator for macOS. Instantly converts between binary, decimal, hex, and octal — with full arithmetic and bitwise shift support.
Download Free — v1.0.1Everything a programmer needs, nothing they don't.
Instantly switch between Binary (BIN), Decimal (DEC), Hexadecimal (HEX), and Octal (OCT) — tap one button to change the active base.
As you type, every number system updates live. Enter 255 in DEC and instantly see FF in HEX and 11111111 in BIN.
Addition, subtraction, multiplication, division, and modulo — all working natively in whichever number base you're currently using.
Left shift (<<) and right shift (>>) operations for bit manipulation, essential for embedded work and low-level programming.
Built with Swift and AppKit. No Electron, no web views. Fast, lightweight, and feels right at home on your Mac.
No in-app purchases, no subscriptions, no telemetry. Download and use forever.
Pick your base, enter a number, watch it convert.
Press HEX, DEC, BIN, or OCT to set the active input mode. The keyboard updates to show only valid digits for that base.
Enter digits as you normally would. In HEX mode, A–F buttons become available. The display shows the value in every base at once.
Use +, −, ×, ÷, % for arithmetic, or << / >> for bitwise shifts. Hit = to evaluate and see the result across all bases.
Change number base at any time — the current value is re-expressed in the new base without losing your calculation context.
Free. No account required.
Version 1.0.1 · Released May 2025
Download B64Calc-1.0.1.dmgVersion history.
Enjoying B64Calc? Let me know what you think — feedback, ideas, and bug reports are always welcome.