A TUI calculator for firmware engineers and PCB designers. Runs in cmd.exe. No install. No electron. No browser. One .exe.
Ohm's law. Voltage dividers. RC constants. Trace widths. UART timing. Bit viewers. Everything you reach for a calculator or random website for — in one keyboard-driven tool.
Written in C. Ships as a single executable. Fits on a USB stick.
EWB runs entirely in the Windows console using the native Console API.
No Electron, no .NET runtime, no installer. Copy ewb.exe
anywhere and run it. It fits on a USB stick next to your other tools.
Designed for people who don't want to lift their hands off the keyboard. arrow keys, Tab to switch focus, number keys to switch tabs, F-keys for actions. Fast once you know it.
Values use engineering notation throughout. Type 4k7,
100n, 2.2M —
EWB understands all of it. Results snap to E12/E24/E96 series values automatically.
Every calculation is logged to the session panel automatically. Export the whole session as plain text. Use it to document your design decisions as you go.
Demo unlocks Ohm's law. License unlocks everything.
License is locked to your machine. Place ewb.lic next to ewb.exe to unlock.
To purchase: email with your machine ID (shown in EWB demo mode session log). License file delivered by email within 24 hours.