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Converters

Free tools in this category, built for quick workflows.

Unit Converter

Convert length, weight, temperature, and area units.

Percentage Calculator

Calculate percentages, increase, and decrease easily.

Tip Calculator

Split bills and calculate tip by percentage.

Loan Payment Calculator

Estimate monthly payment, total interest, and total repayment.

Paycheck Calculator

Estimate gross pay, taxes, and take-home pay for each paycheck.

Pay Raise Calculator

Estimate how a raise changes annual, monthly, and take-home pay.

Time Card Calculator

Track weekly work hours, overtime, and gross pay from clock-in entries.

Overtime Pay Calculator

Calculate regular, overtime, and double-time pay with weekly or California-style daily overtime rules.

1099 vs W-2 Take-Home Calculator

Compare estimated annual value between W-2 and 1099 scenarios with taxes, expenses, and benefits.

Sales Tax Calculator

Calculate tax amount, pre-tax price, and final total in seconds.

Discount + Tax Calculator

Apply discount first, then calculate sales tax and final checkout total.

APR Calculator

Estimate annual percentage rate or monthly payment for a fixed-term loan.

Subscription Waste Finder

Upload CSV and detect recurring charges, duplicates, and possible wasted spend.

Subscription Downgrade Optimizer

Model ad tiers, annual plans, and bundles to cut recurring subscription costs.

Quarterly Tax Safe-Pay Planner

Estimate quarterly tax payments and due-date targets for freelancers and side income.

W-4 Withholding Checkup Calculator

Estimate whether your federal withholding is on track and how much extra withholding may be needed per paycheck.

HSA Contribution & Tax Savings Calculator

Estimate HSA contribution room, catch-up eligibility, and tax savings from payroll or direct contributions.

Mileage Deduction Calculator

Estimate business, medical, and charity mileage value with editable standard-mileage rates and parking/toll adjustments.

Home Electricity Bill Estimator

Estimate a monthly home power bill from state-average electricity rates, kWh usage, fixed fees, and off-peak assumptions.

EV Charging Cost Calculator

Estimate EV charging cost by U.S. state, compare home vs public charging, and benchmark annual EV savings against gas.

EV Trip Charging Cost Planner

Estimate charging stops, charging time, and trip cost for long-distance EV travel.

EV Charge Time Estimator

Estimate charging time and charging cost from start SoC to target SoC.

EV Home Charger Payback Calculator

Estimate Level 2 charger payback period using home/public charging mix and local rates.

EV Battery Degradation Estimator

Forecast EV battery health and expected range decline by usage and climate profile.

Markup & Margin Calculator

Calculate selling price, markup, margin, and profit from cost data.

IB Buying Power Simulator

Estimate remaining stock buying power from A/B/C positions under simplified margin assumptions.

ETF Move Recalculator

Estimate ETF fair move from weighted constituent returns, with sentiment adjustment and backsolve for unmodeled weight.

Options Breakeven & P/L Calculator

Calculate call/put breakeven and expiration profit or loss for single-leg option positions.

Covered Call Return Calculator

Estimate premium income, called-away return, breakeven, and annualized yield for covered calls.

Cash-Secured Put Yield Calculator

Calculate cash-secured put premium yield, breakeven, assignment basis, and annualized return.

Currency Converter

Convert between USD, EUR, GBP, CAD, AUD, JPY, and CNY.

Periodic Table

Browse all chemical elements with search, family filters, and quick element details.