Free calculators for home projects, the yard and your car
Work out concrete, gravel, mulch and soil, square footage and drywall, the BTUs a room needs, what a road trip costs in gas, your real MPG, and how two tire sizes compare.
- Runs on your device, nothing uploaded
- No sign-up, no watermarks
- Works on phone and desktop
All tools
10 tools, all free, all private
Concrete and yard
4 tools
Home projects
3 tools
Car and driving
3 tools
Popular shortcuts
One-click versions of the tools above
Why people use WrenchNook
Measure like a tape
Type 12' 6", 12 ft 6 in or 3.8 m: mix feet, inches, fractions and metric in any field.
What to actually buy
Answers come as bags, sheets, tons and yards, with a waste allowance built in, not just a volume.
Free, no sign-up
No accounts and no limits. Everything runs on your device, and any result can be shared with a link.
Buy the right amount the first time
Pouring a patio or setting fence posts? The concrete calculator turns your measurements into cubic yards and bags. For the yard, the gravel calculator gives tons for a driveway, the mulch calculator counts bags for your beds, and the cubic yard calculator handles soil, sand and fill.
Inside, measure a room with the square footage calculator, order sheets with the drywall calculator, and size an air conditioner with the BTU calculator. On the road, the gas cost calculator prices a trip, the MPG calculator checks your mileage, and the tire size calculator compares sizes before you buy.
Frequently asked questions
Something else? Email hello@wrenchnook.com.
Is WrenchNook free?
Yes. Every calculator is free to use as often as you like. We are supported by ads, which we keep away from the calculators themselves.
How accurate are the material estimates?
The math is exact, and the material figures (bag yields, stone weights, sheet sizes) are the typical published values. Real jobs vary, which is why each result adds a waste allowance you can change. For structural work, follow your plans and local code.
Can I use metric units?
Yes. Every calculator works in feet and inches or in meters and centimeters, and shows results in both where it helps.