Metrics Calculator

Fun & Utility Calculators

Love calculator, password generator, Roman numeral converter, tip calculator, and other handy everyday tools.

Everyday tools for splitting tips, estimating electricity bills, comparing unit prices, generating secure passwords, and more. These calculators handle the small math problems that come up in daily life.

5 calculators available

Which calculator do you need?

For dining out, the tip calculator splits the bill between any number of people and lets you tip on the pre-tax amount. Trying to figure out which size of laundry detergent is the better deal? The unit price calculator compares up to 4 products side by side across different sizes and units.

The electricity cost calculator estimates monthly and yearly costs for any appliance based on wattage and your electric rate. The fuel cost calculator does the same for road trips, factoring in distance, fuel efficiency, and current gas prices. And if you need a strong password, the password generator creates random passwords with entropy ratings so you know exactly how secure they are.

Common questions about these tools

How do I calculate electricity cost per month?

Multiply the appliance wattage by hours used per day, then by 30 days, then divide by 1,000 to get kilowatt-hours (kWh). Multiply that by your electricity rate. For example, a 1,500W space heater running 8 hours a day at $0.13/kWh costs about $46.80 per month. The electricity cost calculator does this math instantly for any appliance.

What tip percentage should I use?

In the US, 15-20% is standard for sit-down restaurants: 15% is considered adequate, 18% is typical, and 20% or more signals great service. For takeout 10% is common, and for delivery 15-20% is expected. Our tip calculator lets you tip on the pre-tax subtotal (which many etiquette guides recommend) and splits the total evenly among your group.

How long should a password be?

At least 12 characters, though 16 or more is better. A 12-character password with uppercase, lowercase, numbers, and symbols has about 79 bits of entropy, which would take centuries to crack with current hardware. Each additional character roughly multiplies the difficulty by 90x. The password generator shows the entropy score for each password so you can gauge its strength.