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Building materials, mortgages and loans, health and fitness, math, science and everyday dates and conversions, with clear formulas, imperial and metric units, and results you can share, save, print or download.

Worked example 12 × 16 ft patio · 4 in

Concrete with 10% waste

2.61yd³

Ready-mix order: 2.75 yd³
Or 80 lb bags: 118
Gravel base, 4 in compacted: 4.09 tons

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Concrete & Masonry Plan a pour from start to finish: size the slab or footing, decide between bags and a ready-mix truck, lay out the rebar and price the job. 7 calculators Landscape & Paving Bulk materials are sold by the ton, the cubic yard, the bag or the pallet. These calculators convert your area and depth into all of them, with typical densities and coverage for each material. 7 calculators Flooring, Tile & Drywall Finish a room without a second trip to the store: count tiles by layout pattern, size the grout, order the right drywall sheets and add up flooring across every room. 6 calculators Outdoor Projects Turn a sketch into a shopping list: every board, post, block and bag of base for a deck, fence, paver patio or retaining wall, with waste and cost. 6 calculators Finance Work out payments, interest, savings and returns with clear formulas and full schedules. Results are estimates; check the details with your lender or a qualified adviser. 76 calculators Health & Fitness Standard, published formulas for body measurements, nutrition, training and pregnancy dates. They are general estimates, not medical advice: talk to a health professional about your situation. 31 calculators Math From fractions and percentages to triangles, statistics and matrices, with the formula and working shown so you can check every answer. 44 calculators Science & Engineering Physics, chemistry, electrical and weather formulas with units handled for you, from Ohm's law to molarity and dew point. 18 calculators Everyday Handy tools for dates, time, school, travel, shopping and the web: quick answers without the clutter. 25 calculators

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Concrete & Masonry 7

Landscape & Paving 7

Flooring, Tile & Drywall 6

Outdoor Projects 6

Finance 76

Math 44

Science & Engineering 18

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Published formulas

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Imperial and metric

Feet and cubic yards or meters and m³. Switch any time and your numbers convert.

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