Tallette: Tape Calculator

A paper-tape calculator: type amounts down the tape as on an adding machine, give each line a comment, and fix any line at any time. The totals below it follow at once.

TYPE AS YOU WOULD SAY IT
• 12.50+ adds, −7.20 lunch subtracts with a comment, 3×4= multiplies, +19% tax adds tax, 15% takes a percentage.
• Subtotals, totals and grand totals, like an adding machine's, and new sections for each part of a job.
• Your region's number format, with a decimal point or comma, and forgiving when you type the other one.

EVERY LINE STAYS EDITABLE
Change an amount ten lines up and everything below it is worked out again. Comments say what each number is; a #tag in a comment totals lines by category: food, rent, travel.

EXACT, TO THE LAST CENT
Tallette counts in decimal, never in binary floating point: 0.10 + 0.20 is exactly 0.30. Results keep 34 significant digits and round half up; dividing by zero shows an error line instead of a wrong number.

TAX, PERCENT AND CURRENCY
• Add or remove VAT or GST at the tape's rate, or type another rate on the line.
• Add or take off a percentage: a tip, a discount, a markup.
• Show a currency beside the totals, with its usual decimals. Nothing is converted and nothing goes online.

A KEYPAD MADE FOR SUMS
Big keys with + − × ÷, %, subtotal, total and tax keys, and a touch of haptics. Type an amount and press + or −, as on an adding machine; × and ÷ chain like a calculator. A note field puts a comment or #tag on the next line. Tap a line to edit it, swipe to delete, and undo anything. A hardware keyboard works too.

YOUR TAPES, ON YOUR DEVICE
Every tape is saved as you go, on your phone or tablet. Save a tape as text, CSV, PDF or a Tallette file wherever you like through the system file picker, share it, or import a CSV or text file of numbers. Phones and tablets, in 34 languages, light and dark.

PRIVATE BY DESIGN
Tallette never connects to the internet. Your tapes stay on your device. No account, no tracking, no analytics.

Requires Android 8.0 or later.