DieselCalcs

DieselCalcs: Financial calculators built for people serious about reaching FIRE (Financial Independence, Retire Early).
100% FREE. NO ADS. NO TRACKING. NO BS.
Powerful, easy-to-use, privacy-first calculators that help you take control of your financial future—without costing you a dime.
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CALCULATORS TO ACCELERATE YOUR FIRE JOURNEY
FIRE Calculator
Calculate your Traditional FIRE number, Coast FI target, and Monte Carlo success probability all in one view. See exactly how much you need to retire and your probability of success.
• Traditional FIRE: Your full retirement number based on annual expenses and withdrawal rate
• Coast FI: How much you need today to coast to retirement without additional savings
• Monte Carlo Success: Your probability of reaching your FIRE goal accounting for market volatility
Buy vs Rent Calculator - NEW!
Finally answer the question: should you buy or rent? Get a clear recommendation based on comprehensive analysis of total costs, opportunity costs, investment returns, mortgage details, and insurance over your timeline.
• Total cost comparison over your stay duration
• Opportunity cost of down payment invested
• Mortgage interest and principal breakdown
• Property taxes, HOA fees, and insurance
• Clear "buy" vs "rent" recommendation
Compound Interest Calculator
Master the math of wealth building with three powerful calculation modes:
• Future Value: See how your money grows with regular contributions
• Required Contribution: Calculate the monthly amount needed to reach your goal
• Years to Goal: Find out how long it takes to hit your target with your current savings rate
Car Payment Calculator - NEW!
Calculate monthly car payments with comprehensive breakdowns. See total interest paid and optimize your loan terms before signing.
• Monthly payment calculations
• Total interest and cost over loan life
• Principal vs interest breakdown
• Compare different loan terms and rates
Inflation Calculator
Adjust dollar amounts for inflation using real CPI data (1913-2024). Understand what your money will be worth in the future, or what past dollars are worth today. Projects 3% annual inflation for future years to help you plan ahead.
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BUILT FOR YOU
Completely Free
Every calculator. Every feature. Zero cost. Built for people who are serious about their money and don't want to waste it on yet another subscription or expensive app.
Privacy First
All calculations happen on your device. We don't collect, store, or transmit any of your data. Ever.
Beautiful UX
Smooth sliders with haptic feedback and an industrial design that feels premium. Results stay visible while you scroll—no more hunting for numbers.
Mobile-Optimized
Built specifically for iPhone with perfect touch targets, intuitive controls, and state persistence that remembers where you left off.
Support Development (Optional)
If you find the app valuable, optional "Buy Me a Matcha" tips are available. But the app is 100% functional without tipping—no guilt, no pressure, no locked features.
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PERFECT FOR
• FIRE community members tracking their journey to financial independence
• Anyone deciding between buying vs renting
• Home buyers calculating mortgage payments and total costs
• Car buyers comparing loan options
• Investors who want to understand compound growth
• People planning for inflation and future purchasing power
• Anyone who's tired of expensive financial apps with subscriptions
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YOUR DATA STAYS YOURS
Zero data collection. Zero third-party tracking. Just calculators that work, respect your privacy, and help you reach financial independence faster.
And now, completely free.
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Built by a developer in the FIRE community, for the FIRE community.