Tahoe Math

Type an expression ending in = and the answer appears right after it, as you type. Define variables and functions, mix units, convert, work out percentages, money and dates, all inside ordinary notes.

What it understands

You type	You see
x = 12 then x * 3.5 =	42
5 km + 300 m =	5.3 km
3 ft to cm =	91.44 cm
72 degF to degC =	22.222 degC
20% of 80 =	16
$12.50 * 4 =	$50.00
f(t) = t^2 + 1 then f(4) =	17
daysUntil("Dec 25") =	the days left

Variables and functions carry down the note, so later lines can use earlier ones. Answers are worked out exactly by math.js, not guessed.

Using it

• Answers show as you type. Nothing is written into your note until you want it.
• Keep an answer: click it, or press Tab at the end of the line, and it's written in.
• Write every answer in at once: run Write all answers into this note from the command palette.
• Reading view shows the answers too.
• Only where you want it: turn on Only in notes marked for maths in the settings, then add math: true to the properties of the notes that should show answers.
• Precision: choose how many significant digits answers show.

It uses nothing desktop-only, so it runs in Obsidian on phones and tablets too.

Questions in plain English (optional)

With the companion plugin Tahoe Intelligence (Mac only, not in the community directory yet), you can also type questions like days until Oct 14 = or 20% tip on $86 split 3 ways =. An on-device model rewrites the question as a calculation, and Tahoe Math works it out exactly. These answers are marked with ✦. Without Tahoe Intelligence, everything else works as normal.

Disclosures

• No network use. Tahoe Math works entirely offline.
• No files outside your vault. Its settings, and any plain-English rewrites, are saved in the plugin's own data in your vault.
• No telemetry, ads, accounts or payments.

Credits

math.js by Jos de Jong does the arithmetic, under the Apache License 2.0. See THIRD_PARTY_NOTICES.md.

Tahoe Math is an independent project. It isn't affiliated with, or endorsed by, Apple.

License

MIT © 2026 Krishnan Adaikkappan

Building from source

npm ci
npm run build     # writes main.js

Releases are built by GitHub Actions: push a tag that matches the version in manifest.json, then publish the draft release it creates.