All Free Online Calculators
Browse the full collection of free calculators for finance, health, math, conversions and everyday decisions. Search instantly or jump straight to a category.
Compare commute costs per person when you share the ride.
Add up what your monthly and yearly subscriptions really cost.
Estimate weekly study hours from your credit load.
Count posts, rails, and pickets for a fence run.
Cubic yards and bags needed to cover a garden bed.
Measure how many staff leave relative to your average headcount.
Turn visits and orders into conversion rate and revenue metrics.
Force from mass and acceleration, with speed and distance after a time.
Find how much stock solution you need for a target concentration.
Total hydration, salt, and starter percentages for sourdough.
Total ownership cost of a vehicle per distance unit driven.
Estimate aerobic fitness from a 12 minute run.
Subnet mask and usable host count for a CIDR prefix.
Driving time with rest stops, plus fuel cost for the trip.
Estimate the solar array size and number of panels your home needs.
Daily, monthly, and yearly energy from a set of solar panels.
How many years a solar system takes to pay for itself.
Pick the right charge controller current for your panels and battery bank.
How long a battery can power a load.
Size a battery bank for off-grid or backup power.
Estimate how long a battery takes to charge.
How many times a power bank can charge your phone.
Savings from replacing old bulbs with LEDs.
What devices cost you while idle or on standby.
Will a more efficient appliance pay for itself?
Add up the daily energy use of several appliances.
Real, apparent, and reactive power from volts and amps.
Power in kW and kVA for a three-phase supply.
Convert kVA to kW and current for single or three-phase supplies.
Capacitor size needed to improve power factor.