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Financial Calculators for Smarter Decisions

Professional-grade calculators built for crypto traders, prediction market players, and modern investors. Free, instant, no sign-up required.

Prediction Market & Trading
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Bankroll

Kelly Criterion Calculator

Calculate the optimal position size for any prediction market or trading decision. Maximize long-term growth without risking ruin.

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Analysis

Expected Value Calculator

Instantly compute EV, edge %, and implied probability for any binary-outcome trade on Polymarket or other prediction platforms.

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Risk

Position Size Calculator

Find the right trade size based on your account balance, risk tolerance, and stop-loss distance. Works for crypto and prediction markets.

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Crypto & Investing
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Investing

Compound Interest Calculator

Visualize how your crypto or investment portfolio grows over time with compounding. Adjust frequency, rate, and contributions.

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Tax

Crypto Tax Estimator

Estimate capital gains tax on crypto trades. Supports short-term vs long-term rates, and links to CoinLedger for full reporting.

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Convert

Crypto Converter

Real-time crypto-to-crypto and crypto-to-fiat conversion. BTC, ETH, SOL, USDC, and 100+ assets. Swap via ChangeNOW.

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Currency

Currency Converter

Live exchange rates for 160+ fiat currencies. USD, EUR, GBP, JPY, AED, and more. Updated every hour from open APIs.

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Inflation

Inflation-Adjusted Return

See your real returns after inflation. Convert nominal gains to purchasing-power-adjusted growth. Critical for long-term crypto holders.

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