numbr

A natural-language calculator for Linux/Wayland, optimized for Hyprland. Inspired by Numi, with a focus on developer workflows.

10 km in miles                   6.21371 miles
sqrt(2) * 3                      4.242640687
0xFF in binary                   0b11111111
255 as int16                     -1
price = 42; price * 3            126
modbus::float32(0x4128, 0x0000)  10.5
today + 2 weeks                  2026-07-18

Features

• Arithmetic, percentages (5% of 200, price - 20%), variables, line references (line1)
• Scientific functions: sqrt, sin, cos, tan, log, ln, exp, abs, …
• Number systems: 0xFF, 0b1010, 0o17 — convert with in hex, in binary, in octal
• Bit widths: 255 as int8 → -1 (two's complement), 0xFFFF as int16 → -1
• Bit operations: &, |, ^, ~, <<, >>, popcount, clz, ctz
• Modbus register conversion: modbus::float32, modbus::int32, modbus::uint32, word-order variants
• Unit conversion: length, mass, temperature, pressure, data size, time
• Date arithmetic: today + 2 weeks, diff(2026-07-04, 2026-01-01) in days
• Session persistence: last session is automatically restored on startup
• Clipboard: click any result to copy it

Build

cargo build --release

The binary is placed at target/release/numbr.

Hyprland integration

Add to your hyprland.lua (or any file you require from it):

-- Launch numbr with Super+Shift+C
hl.bind("SUPER + SHIFT + C", hl.dsp.exec_cmd("numbr"), { description = "Calculator" })

-- Float it, centre it, give it a fixed size
hl.window_rule({
    match  = { class = "^(numbr)$" },
    float  = true,
    size   = { 680, 520 },
    center = true,
})

Close the window when you are done — your session is saved automatically and restored next time you open numbr.

Usage tips

• Multi-line notebook — each line is evaluated independently; previous results are accessible as line1, line2, …
• Variables — price = 42; price * 3
• Comments — lines starting with # are ignored
• Clipboard — click any result in the right column to copy it