Compound Interest Calculator
Model compound interest with configurable principal, rate, compounding frequency, and additional contributions. Interactive growth chart with year-by-year breakdown.
The Finance Knife for Founder / Business Owners
Money maths — no spreadsheet required
Run your business with tools you own. The Finance Knife gives founder / business owners 10 specialised tools in a single HTML file that runs entirely offline.
The Finance Knife puts six essential financial calculators and a Scenario Studio into a single HTML file. Model compound interest with Oracle Mode (reverse-engineer your savings goal) and Monte Carlo simulation (see probability-weighted outcomes under volatility). Generate loan amortisation schedules with extra-payment analysis, calculate IRR and NPV, reference 20 currency exchange rates, split VAT inclusively or exclusively, and generate printable invoices — all locally in your browser. Global inflation adjustment lets you see every result in today's dollars. Your financial data never touches a server.
WHAT'S INSIDE
10 tools in a single HTML file
Oracle Mode
Reverse-engineer your financial goals — enter a target amount and get three paths (conservative, balanced, aggressive) showing the monthly contribution needed to reach it.
Monte Carlo Simulation
Run 1,000+ randomised simulations with configurable volatility to see probability-weighted outcome bands. Shows 10th/25th/50th/75th/90th percentiles and goal success probability.
Loan Amortiser
Generate full amortisation schedules for any loan — see principal vs interest breakdown for each payment, total interest paid, payoff date, and savings from extra payments.
HOW IT WORKS
Three steps. No setup.
1
Download the file
Purchase The Finance Knife and download a single HTML file. No installer, no account, no setup.
2
Open in any browser
Double-click to open in Chrome, Firefox, Safari, or Edge. Works on any operating system.
3
Start working
Your data stays in your browser's local storage. Nothing is uploaded. Ever.
COMPLIANCE & GEOGRAPHY
Global
Works in any country. No server dependency, no regional restrictions.
FAQ
Frequently Asked Questions
Why should Founder / Business Owners use The Finance Knife?
The Finance Knife is built for founder / business owners who need finance & business tools without cloud dependencies. Compound interest with Oracle Mode and Monte Carlo simulation, loan amortiser, IRR/NPV calculator, currency table, VAT/tax splitter, invoice generator, and Scenario Studio. Financial tools that never share your numbers.
Does The Finance Knife work offline?
Yes. The Finance Knife is a single HTML file that runs entirely in your browser. No internet connection required. Your data never leaves your machine.
Is The Finance Knife a subscription?
No. The Finance Knife is a one-time purchase ($39). No monthly fees, no renewals, no price increases.
What tools are included in The Finance Knife?
The Finance Knife includes 10 tools: Compound Interest Calculator, Oracle Mode, Monte Carlo Simulation, Loan Amortiser, IRR/NPV Calculator, Currency Reference Table, VAT/Tax Splitter, Printable Invoice Generator, Scenario Studio, Inflation Adjustment. All accessible from a single HTML file.
Can I try The Finance Knife before buying?
Yes. Every product page includes an interactive demo you can try in your browser. No signup required.
No cloud One fileOne-time purchase
Get The Finance Knife — $39Sovereignty as a Service