New · iPhone, iPad and Mac
Solve for anything. See why.
Every worksheet a professional financial calculator has — loans, cash flow NPV and IRR, bonds, depreciation, statistics — without memorising N, I/YR, PV, PMT, FV keystroke sequences. Pick what you want to find, fill in what you know.
12 payments a year · End Mode. Switch to start of period and watch the payment drop to $486.52 — that's the setting behind most “wrong answer” complaints.
Everything a financial calculator does
Laid out as plain-language questions with the professional textbook terms beside each, so finance students and industry veterans can both work at full speed.
Loans and mortgages
Payment, rate, amount, term or balloon — solve for any one. P/YR 1 to 365, start or end of period.
Amortization
By month or by year, with due dates, a principal-vs-interest chart and the payment where principal takes over.
Cash flow
NPV, NFV, IRR, MIRR and payback on uneven flows, with repeats grouped and an interactive cash flow diagram.
Savings & retirement
What you'll have, what you must save for a goal, and a 401(k) / provident fund with employer match and cap.
Bonds
Price from yield or yield from price, accrued interest, dirty price, actual/actual or 30/360 day count.
Depreciation
Straight line, declining balance, sum-of-years digits and MACRS schedules, calculated year by year.
Business percent
Margin, markup, percent change and break-even units — the margin-vs-markup mix-up, permanently prevented.
Interest & dates
Nominal to effective rate and back. Exact days between dates, 30/360 day count conventions, add or subtract days.
Statistics & regression
Weighted mean, standard deviations, linear regression with visual fit, and column totals for x and y.
Equation entry
Type full expressions directly: parentheses, powers, roots, natural logs, trigonometry, factorials, nPr, and nCr.
Registers & memory
All 20 memories (M0–M9, M10–M19) and the core financial registers on one screen. Recall, store, and clear in one tap.
History & export
Every calculation is saved automatically with the settings it used. Name it, pin it, reopen anytime, and export PDF or CSV.
Why answers “don't match” — and why they will here
When a calculator's result differs from a lender's schedule or a textbook answer key, the arithmetic is almost never wrong. A hidden setting was different.
| What usually goes wrong | What 10B Calc does differently |
|---|---|
| Payments per year (P/YR) left at an invisible default you didn't choose | Shown prominently next to every answer, editable in a single tap |
| Start vs end of period (annuity mode) buried in a deep menu you never opened | A prominent toggle directly on the worksheet itself, visible in the status bar |
| Actual/actual vs 30/360 day count disparity on bonds and date calculations | Convention clearly labeled right beside the result and saved with your work |
| A decimal comma read mistakenly as a thousands separator in different regions | Numbers dynamically follow your locale with an instant live preview in Settings |
| Closing or backgrounding the app completely wipes your active work | Every calculation is saved to persistent History with the exact settings it used |
One purchase, three devices
Buy it once and it is yours across your iPhone, iPad, and Mac — with full Family Sharing support.
iPhone
Focused single-worksheet view, large readable answers, and all mode settings immediately underneath.
iPad
Multi-column productivity: worksheets, live solver, and History side by side. Full support for Magic Keyboard and Apple Pencil.
Mac
A native macOS application with full menu bar support, multiple independent windows, AirPrint, and complete keyboard navigation.
Pro Keyboard Shortcuts (Mac & iPad)
- Every single worksheet included — zero locked features, zero upsells
- No subscriptions, no recurring charges, no advertising
- Completely offline — nothing you calculate ever leaves your device
- Apple Family Sharing enabled for up to 5 family members
- Native universal build for iPhone, iPad, and Apple Silicon / Intel Mac
Frequently asked questions
Is it an exact replica of a physical 10B or 12C hardware calculator?
No. It performs the exact same verified financial arithmetic, but replaces tedious multi-key button sequences with clean, modern worksheet cards. If you specifically need key-for-key hardware emulation with tiny segmented LCD numbers, this is designed to be much better.
Will my calculated answer match my loan officer or bank?
Yes, provided the compounding frequency and timing settings match. Banks occasionally add undisclosed administrative fees into the financed principal or round odd cents differently. Our mismatch diagnostic guide allows you to verify and locate differences in under one minute.
Does 10B Calc work offline?
100% offline. There is no account registration, no login requirement, and the app executes zero background network queries. All your calculations remain strictly on your own hardware.
Can I bring this into financial certification exams (CFP, CFA, etc.)?
Check your specific testing board's rules. Most in-person proctored testing rooms require standalone battery-powered physical hardware with no network radios. 10B Calc is built for study, coursework preparation, office analysis, and field consultations.
Does 10B Calc offer financial advice?
No. 10B Calc is an arithmetic calculation utility for planning and estimation. Results do not constitute formal financial, investment, accounting, or tax advice.
Support and Documentation
Need assistance or want to verify a complex worksheet? Explore our resources:
Support & Troubleshooting Guide · Privacy Policy · Copyright & Terms
A financial software product by Finmak Softwares · Chennai, India · admin@finmaksoftwares.in