PDFAITools
318+ Free Online Tools
Browse 318+ free tools across PDF, SEO, calculators, image editing, text and more — no account needed.
318
Free Tools
Ratio Calculator
Simplify ratios, solve proportions and scale ratios up or down.
Finance & Calculators
Use free →
Rounding Calculator
Round numbers using half-up, half-even, ceiling, floor or truncation — all methods shown at once.
Finance & Calculators
Use free →
Scientific Notation Calculator
Convert numbers to and from scientific notation and perform multiplication/division.
Finance & Calculators
Use free →
Sample Size Calculator
Calculate the required sample size for any population at your desired confidence level and margin of error.
Finance & Calculators
Use free →
Percent Error Calculator
Calculate percent error, absolute error and relative error between experimental and theoretical values.
Finance & Calculators
Use free →
Exponent Calculator
Calculate powers and roots for any base and exponent including decimals and negatives.
Finance & Calculators
Use free →
Half-Life Calculator
Calculate radioactive decay, remaining quantity and half-lives elapsed. Includes substance presets.
Finance & Calculators
Use free →
Distance Calculator
Calculate distance between two coordinate points in 2D or 3D using Euclidean and Manhattan distance.
Finance & Calculators
Use free →
P-Value Calculator
Calculate p-value for Z, T, Chi-square and F test statistics with one-tail and two-tail options.
Finance & Calculators
Use free →
Day of the Week Calculator
Find the day of the week for any date. Shows ISO week number, day of year and quarter.
Finance & Calculators
Use free →
Grade Calculator
Calculate your weighted grade average or find what score you need on your final exam.
Finance & Calculators
Use free →
Golf Handicap Calculator
Calculate your WHS golf handicap index from score differentials using the World Handicap System.
Finance & Calculators
Use free →
Random Number Generator
Generate random numbers in any range, roll dice (d4–d100) or flip a coin.
Finance & Calculators
Use free →
Fuel Cost Calculator
Calculate fuel cost for any trip based on distance, fuel efficiency and petrol price.
Finance & Calculators
Use free →
Gas Mileage Calculator
Calculate MPG and L/100km from odometer readings or direct distance and fuel amount.
Finance & Calculators
Use free →
Wind Chill Calculator
Calculate wind chill temperature using the NWS formula and see frostbite risk levels.
Finance & Calculators
Use free →
Heat Index Calculator
Calculate the heat index (feels-like temperature) from temperature and humidity.
Finance & Calculators
Use free →
BTU Calculator
Calculate BTU needed to heat or cool a room, or convert BTU to kWh, joules and calories.
Finance & Calculators
Use free →
Voltage Drop Calculator
Calculate voltage drop in electrical wire runs for any gauge, length and current.
Finance & Calculators
Use free →
Resistor Calculator
Decode resistor colour bands (4 or 5 band) and calculate series/parallel resistance.
Finance & Calculators
Use free →
Ohm's Law Calculator
Calculate voltage, current, resistance and power using Ohm's Law. Solve for any unknown.
Finance & Calculators
Use free →
Horsepower Calculator
Calculate engine horsepower from torque and RPM, or convert HP to kW, PS and more.
Finance & Calculators
Use free →
Density Calculator
Calculate density, mass or volume using D = M/V. Includes a common materials reference table.
Finance & Calculators
Use free →
Bandwidth Calculator
Calculate download time, required bandwidth speed or monthly data cap usage.
Finance & Calculators
Use free →
No tools match "" on this page.