Calculators tools
Everyday calculators and converters.
Free calculators for home, finance, and everyday math
ToolHub's calculator collection covers the construction and personal-finance math people actually search for: how much concrete for a slab, how many gallons of paint for a room, how many bundles of shingles to roof a house, what a monthly mortgage payment looks like after taxes and insurance. Every calculator runs in your browser — no signup, no uploads, no ads-walled paywall. Built from US building-code spacing standards, current contractor pricing surveys, and the same formulas suppliers use to quote you over the phone.
Calculators by project
Pick the project you're working on — we'll show every calculator you'll likely need, in the order you'll need them.
Building a deck or patio
Plan a backyard upgrade end to end: framing, footings, fencing, paint, and the gravel base.
Remodeling a kitchen or bathroom
Interior remodels need tile, drywall, flooring, paint, and often new finance numbers to go with them.
Landscaping a yard
Mulch beds, gravel paths, a new fence, and the patio surface — all on one page.
Financial planning
Mortgages, age math, and percentage calculations for everyday personal finance decisions.
Replacing a roof
Roof replacement involves squares, bundles, underlayment, and often touches every adjacent system.
Adding a fence or driveway
Hardscape projects share concrete and gravel needs — and almost always need a fresh paint or stain step at the end.
Popular questions answered by these calculators
Common search queries that land on the right tool with one click.
- How many bags of concrete for a 10x10 slab?
- How much paint for a 12x12 room?
- How many gallons of paint per gallon coverage?
- How much mulch do I need for a 10x10 bed?
- How many tiles for a 5x8 bathroom?
- How much does a 12x16 deck cost?
- How many shingles per square?
- How many fence posts for 100 ft?
- How much gravel for a 20x40 driveway?
- How many drywall sheets per room?
- How much flooring for a 12x14 room?
- What's the monthly payment on a $400k mortgage?
All Calculators tools
Mortgage Calculator
Monthly payment, total interest, and full amortization schedule
Age Calculator
Exact age in years, months, days, and more
Percentage Calculator
Every common percentage calculation, instantly
Concrete Calculator
Bags, yards, and cost — slabs, footings, and more
Paint Calculator
Gallons of paint for any room
Mulch Calculator
Cubic yards and bags for any garden bed
Flooring Calculator
Square feet, boxes, and cost for any room
Fence Calculator
Posts, panels, concrete, and cost
Gravel Calculator
Tons, cubic yards, and bags for driveways and paths
Tile Calculator
Tiles, grout, and cost for any floor or wall
Drywall Calculator
Sheets, screws, mud, and tape for any room
Deck Calculator
Boards, joists, posts, and cost for any deck
Roofing Calculator
Squares, bundles, underlayment, and cost
BMI Calculator
Body Mass Index with healthy weight range
Tip Calculator
Tip + total + split between any number of people
Loan Calculator
Auto, student, personal, home-equity — with amortization
Compound Interest Calculator
Project savings with regular contributions and any compounding frequency
GPA Calculator
Semester + cumulative GPA across multiple grade scales
Calorie Calculator
TDEE, BMR, and daily calorie target with macros
Sales Tax Calculator
Add or reverse sales tax / VAT / GST with state presets
Discount Calculator
Percent off, sale price, stacked discounts, you-save amount
Date Duration Calculator
Days between dates, plus add or subtract from a date
Scientific Calculator
Trig, logs, powers, factorial — with keyboard input and history
Statistics Calculator
Mean, median, mode, range, and standard deviation
Fraction Calculator
Add, subtract, multiply, divide — with steps and simplification
Aspect Ratio Calculator
Solve dimensions for 16:9, 4:3, and any ratio
Timer & Stopwatch
Countdown timer, stopwatch, and Pomodoro in one
Hours Calculator
Time between two clock times, plus timesheets
Salary Calculator
Convert pay between hourly, weekly, monthly, and annual
Fuel Cost Calculator
Trip fuel and cost from distance, economy, and price
Pregnancy Due Date Calculator
Estimate your due date from LMP, conception, or IVF
Ovulation Calculator
Find your fertile window and ovulation days
Body Fat Calculator
Estimate body fat % with the US Navy method
Looking for something else?
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