Make quick, confident
decisions — every day.
Free online calculators and utility tools for finance, health, math, and daily life. No sign-up, no downloads, no nonsense. Just answers you can trust.
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Pick what you need. We'll handle the math.
Editor's Choice
Tools we keep bookmarking for ourselves.
NPV Calculator
"The one tool I send to every founder who asks 'should I take this deal?' — clean, fast, no nonsense."
HealthFasting Window Calculator
"Finally a fasting tool that doesn't try to sell me supplements. Just tells me when to eat. Perfect."
MathFraction Calculator
"My kid's homework got harder than I remembered. This saved an entire evening of tears — mine and theirs."
HomeHome Sale Profit
"Helped me realize the 'profit' on my house was way less than I thought after closing costs. Reality check, delivered gently."
ConversionHex to RGB Converter
"I use this almost daily for design work. It's faster than any color picker I've tried."
GamingGuild Boss HP Calculator
"Our guild went from guessing to strategizing overnight. Turns out we were over-committing by 40%."
Fresh Tools
Just added. Still warm.
0-60 Time Estimator
Estimate your car's 0-60 sprint based on power and weight.
NEWBamboo Growth Rate
How fast will that bamboo actually spread in your yard?
NEWSkincare Routine Timing
Space out your serums and moisturizers the right way.
NEWEvening Routine Planner
Build a wind-down routine that actually fits your evening.
NEWExam Countdown
Days, hours, minutes until your next test. Stay honest.
NEWBaby Kick Count Tracker
Track fetal movements with a simple tap counter.
NEWKefir Grain to Milk Ratio
Get the fermentation balance right every batch.
NEWKombucha Brewing Ratio
Tea, sugar, starter — measured so your booch doesn't flop.
NEWCat Age Calculator
Convert your cat's age to human years — properly.
NEWCider Fermentation Timeline
Estimate when your homemade cider will be ready.
NEWHeat Pump Efficiency
Compare heat pump COP and see real energy savings.
NEWGRE Score Calculator
Estimate your scaled GRE score from raw practice results.
NEWDaylight Hours Calculator
How much sun are you really getting? Check by your city.
NEWBread Dough Calculator
Baker's percentages made simple. Scale any recipe.
NEWChild Height Predictor
Estimate adult height based on parents and growth data.
NEWPregnancy Weight Gain
Track healthy weight gain through each trimester.
What People Say
Real users, real numbers.
I was manually calculating hourly rates in a spreadsheet every time a client asked. Now I punch it into QuickTool and get the number in 10 seconds. I've quoted 23 projects this month without second-guessing.
Saved ~3 hours/week on quotingThe pregnancy weight gain and kick count tools were exactly what I needed at 2am when the doctor's office was closed. No app to install, no login. Just answers.
Used 4 different tools during pregnancyI used the markup-vs-margin and effective-tax-rate calculators before pricing our new product line. Turns out my gut was off by about 8%. That's real money on a 6-figure product.
Avoided an 8% pricing mistakeQuestions We Get a Lot
The stuff people actually ask, not the stuff we wish they'd ask.