Back to all apps
CalcBook — Calculator Notepad
Your notepad that does the math. Type in plain English, get instant answers.
Download nowv1.2.0
Your notepad that does the math. Type in plain English, get instant answers.
CalcBook is a natural language calculator for Android. Instead of tapping buttons on a grid, you write freely — mixing words, numbers, units, currencies, and dates — and CalcBook figures out the math. Words are ignored. Values are calculated. Results appear instantly on the right side of every line.
If you've ever wanted Soulver or Numi on Android, CalcBook is built for you. It works fully offline, has zero tracking, and stores everything locally on your device.
Type the way you think. Words are skipped, values are calculated automatically.
coffee $4.50 and muffin $3.00 → $7.50
Add, subtract, find of, find what %, or out-of — it all works in plain English.
$200 + 15% → $230.00
30% of 950 → 285
45 out of 60 → 75%
Built-in rates for $, €, £, ¥, ₹ and all ISO codes. No internet required.
1500 INR in USD → ~$18.00
Length, weight, volume, temperature, speed, area, data, energy and more.
100 km in miles → 62.14 miles
30°C in °F → 86°F
Add days to dates, find days between, do arithmetic on times.
Jan 1 + 133 days → May 13, 2025
9:00 AM + 90 min → 10:30 AM
Define once, reuse anywhere. A live total bar shows the sum of all results.
rate = $35
40 hours * rate → $1,400.00
Lines starting with // are ignored — use them as section headers for clean notes.
Copy as formatted text, share via system share sheet, or export as a styled PNG card.
No Firebase, no analytics, no tracking. Everything stays on your device.
| Feature | Regular calculator | Spreadsheet | CalcBook |
|---|---|---|---|
| Natural language input | No | No | Yes |
| Mixed units & currency | No | Manual | Yes |
| Date arithmetic | No | Complex | Yes |
| Variables | No | Yes | Yes |
| Works fully offline | Yes | No | Yes |
| Reads like a notepad | No | No | Yes |
CalcBook is a natural language calculator app for Android. Instead of pressing buttons, you type freeform text mixing words, numbers, units, currencies, and dates — and results appear instantly on the right side of each line.
Yes. CalcBook is free with ads and offers a Pro upgrade for $2.99 (one-time, price may vary as features gets added) that removes ads, unlocks unlimited documents, custom syntax themes, editor fonts, font-size control, and watermark-free image exports.
Yes. CalcBook works fully offline. Currency exchange rates and unit conversions are bundled into the app, so you don't need an internet connection for any feature.
Yes. CalcBook is inspired by Soulver and Numi but built specifically for Android. It brings the same natural language calculator experience — type like a notepad and see live results — to Google Play.
Invoices, freelance rates, expenses, currency conversions, unit conversions (km to miles, °C to °F, etc.), date math (days between dates), percentages, splits and tips, and any mixed-format math you can express in plain English.