Calculator N

Calculator N — calculation, done with care.

▸ Edit any part of your expression
Halfway through a long calculation and spot a wrong number? Tap it to select it, type the new value, and it's replaced — everything before and after stays as it was. The full expression stays on screen while you type, and the result updates as you go. Large numbers get thousands separators automatically, and you can choose how many decimal places to keep, from 0 to 10. Tap the result to copy it.

▸ Every calculation is saved
Each time you press equals, the calculation is saved automatically and shown on the calculator screen, grouped by date. Tap a record to insert its result into your current expression, recalculate the whole expression, add a note, copy it, or delete it. If you clear your records, you can restore them once. A separate History page keeps your older calculations.

▸ Six handy tools
· Currency Converter: Convert between common currencies, shown side by side, with one-tap swap.
· Amount in Words: Turn a number into its Chinese uppercase form (大写金额) for receipts and contracts. Tap to copy.
· BMI: Choose from four reference standards — China, Asia-Pacific, WHO, and US. A scale shows whether you're underweight, normal, or above the healthy range.
· Mortgage Calculator: Commercial loans based on LPR plus a spread, as well as Housing Provident Fund loans. Supports both equal installments and equal principal. See your monthly payment, total interest, and total repayment at a glance, and expand to view principal and interest for each month.
· Interest & Returns: Savings interest (simple or compound), investment returns (lump sum or monthly contributions), and compound future value.
· Date Tools: Calculate age and lunar birthday from a date of birth; find the time between two dates; count days, weeks, or months forward or back from any date; convert Gregorian dates to the Chinese lunar calendar.

▸ Look and feel
14 theme colors — keys and highlights change together — plus Dark Mode. Key sounds, haptic feedback, and voice readout can each be turned on separately, and voice readout won't interrupt music that's playing. Add it to Control Center to open the calculator with one tap.

Currency, mortgage, interest, and BMI results are for reference only.