Home & DIY Calculators
Free home and DIY calculators: paint, wallpaper, flooring, tile and carpet estimates for a room; concrete, gravel, mulch and soil by the yard, bag or ton; garden beds, fences, deck boards, stairs, roof pitch and area, board feet and even screw spacing. One coverage-and-waste engine backs the material pages, so a flooring box count and the tile count it sits beside were computed the same way. Every buy count is rounded up — a fraction of a gallon or bag cannot be bought — and every waste default is editable rather than demanded.
Most popular
- home-diyPaint● ready
Enter the room dimensions, doors and windows, coats and the coverage on the can to get gallons needed — with the wall area worked shown.
- home-diyConcrete● ready
Pick the pour shape, enter the dimensions, and read cubic yards plus a bag count at the yield of the bag size you choose (60 lb, 80 lb…).
- home-diyFlooring● ready
Enter the floor area and the coverage per box to get boxes needed, with an editable waste percentage (10% standard, 15% for diagonal) shown in the working.
- home-diyTile● ready
Enter the area, tile size, grout width and waste allowance to get the tile count — the grout line is part of each tile's pitch, so small tiles don't under-order.
- home-diyRoof Pitch● ready
Enter the rise over run (any units, same for both) to get the conventional x:12 pitch, the angle in degrees, and the slope multiplier roof area needs.
Rooms & Coverings
- home-diyRoom Area● ready
Enter the length and width to get the floor area in square feet and square metres — with an optional subtracted rectangle for L-shaped rooms.
- home-diyRoom Volume● ready
Length × width × height in cubic feet and cubic metres — the number air conditioners, purifiers and heaters are sized against.
- home-diyPaint● ready
Enter the room dimensions, doors and windows, coats and the coverage on the can to get gallons needed — with the wall area worked shown.
- home-diyWallpaper● ready
Enter the wall area, ceiling height and roll dimensions to get strips per roll, strips needed and rolls to buy — with the pattern repeat added to every strip.
Floors & Tiles
- home-diyFlooring● ready
Enter the floor area and the coverage per box to get boxes needed, with an editable waste percentage (10% standard, 15% for diagonal) shown in the working.
- home-diyTile● ready
Enter the area, tile size, grout width and waste allowance to get the tile count — the grout line is part of each tile's pitch, so small tiles don't under-order.
- home-diyCarpet● ready
Enter the room size and roll width (12 or 15 ft are standard) to get the seamed length to order, the seam count, and the area in square yards for pricing.
Bulk Materials
- home-diyConcrete● ready
Pick the pour shape, enter the dimensions, and read cubic yards plus a bag count at the yield of the bag size you choose (60 lb, 80 lb…).
- home-diyGravel● ready
Enter the area and depth in inches to get cubic yards, plus tons at the material's density — loose dry, compacted, pea gravel and sand are preset.
- home-diyMulch● ready
Enter the bed area and depth in inches to get cubic yards and the bag count at 2 or 3 ft³ — with the 2–4 inch depth guidance built into the defaults.
- home-diySoil● ready
Enter the bed dimensions and fill depth to get cubic yards and bag counts — vegetables want 8–12 inches, and settle is accounted for in the guidance.
Outdoors & Structure
- home-diyGarden Bed● ready
Enter the bed size and plant spacing to get the plant count, rows and plants per row — spacing is clearance, so counts floor rather than round.
- home-diyFence● ready
Enter the total run, post spacing and gate count to get the post count (with the far-end post the estimates forget), panels, and concrete bags per post.
- home-diyDeck Boards● ready
Enter the frame size, board width, gap and stock length to get rows, boards per row and the count to buy — boards run the longer way to cut waste.
- home-diyStairs● ready
Enter the total rise and a target riser height to get the step count and the true riser height, plus tread depth from the run, stringer length, and a flag against the IRC 7¾-inch limit.
- home-diyRoof Pitch● ready
Enter the rise over run (any units, same for both) to get the conventional x:12 pitch, the angle in degrees, and the slope multiplier roof area needs.
- home-diyRoof Area● ready
Enter the house footprint and the pitch to get the sloped surface area, the slope factor applied, and the area in squares (100 ft²) the way roofers quote.
Workshop
- home-diyBoard Feet● ready
Enter nominal dimensions and the piece count to get board feet per piece and total, with an optional cost at the yard's price per board foot.
- home-diyScrew Spacing● ready
Enter the board length and screw count to get each position in inches from the left end, with the end screws half a bay inside the edge offset so the layout reads even.
All tools
- home-diyRoom Area● ready
Enter the length and width to get the floor area in square feet and square metres — with an optional subtracted rectangle for L-shaped rooms.
- home-diyRoom Volume● ready
Length × width × height in cubic feet and cubic metres — the number air conditioners, purifiers and heaters are sized against.
- home-diyPaint● ready
Enter the room dimensions, doors and windows, coats and the coverage on the can to get gallons needed — with the wall area worked shown.
- home-diyWallpaper● ready
Enter the wall area, ceiling height and roll dimensions to get strips per roll, strips needed and rolls to buy — with the pattern repeat added to every strip.
- home-diyFlooring● ready
Enter the floor area and the coverage per box to get boxes needed, with an editable waste percentage (10% standard, 15% for diagonal) shown in the working.
- home-diyTile● ready
Enter the area, tile size, grout width and waste allowance to get the tile count — the grout line is part of each tile's pitch, so small tiles don't under-order.
- home-diyCarpet● ready
Enter the room size and roll width (12 or 15 ft are standard) to get the seamed length to order, the seam count, and the area in square yards for pricing.
- home-diyConcrete● ready
Pick the pour shape, enter the dimensions, and read cubic yards plus a bag count at the yield of the bag size you choose (60 lb, 80 lb…).
- home-diyGravel● ready
Enter the area and depth in inches to get cubic yards, plus tons at the material's density — loose dry, compacted, pea gravel and sand are preset.
- home-diyMulch● ready
Enter the bed area and depth in inches to get cubic yards and the bag count at 2 or 3 ft³ — with the 2–4 inch depth guidance built into the defaults.
- home-diySoil● ready
Enter the bed dimensions and fill depth to get cubic yards and bag counts — vegetables want 8–12 inches, and settle is accounted for in the guidance.
- home-diyGarden Bed● ready
Enter the bed size and plant spacing to get the plant count, rows and plants per row — spacing is clearance, so counts floor rather than round.
- home-diyFence● ready
Enter the total run, post spacing and gate count to get the post count (with the far-end post the estimates forget), panels, and concrete bags per post.
- home-diyDeck Boards● ready
Enter the frame size, board width, gap and stock length to get rows, boards per row and the count to buy — boards run the longer way to cut waste.
- home-diyStairs● ready
Enter the total rise and a target riser height to get the step count and the true riser height, plus tread depth from the run, stringer length, and a flag against the IRC 7¾-inch limit.
- home-diyRoof Pitch● ready
Enter the rise over run (any units, same for both) to get the conventional x:12 pitch, the angle in degrees, and the slope multiplier roof area needs.
- home-diyRoof Area● ready
Enter the house footprint and the pitch to get the sloped surface area, the slope factor applied, and the area in squares (100 ft²) the way roofers quote.
- home-diyBoard Feet● ready
Enter nominal dimensions and the piece count to get board feet per piece and total, with an optional cost at the yard's price per board foot.
- home-diyScrew Spacing● ready
Enter the board length and screw count to get each position in inches from the left end, with the end screws half a bay inside the edge offset so the layout reads even.
About Home & DIY Calculators
DIY material estimates fail in predictable ways: the coats forgotten in a paint estimate, the pattern repeat dropped from wallpaper, the grout line left out of a tile count, the far-end post missing from a fence run, the roll width ignored when carpet is priced by the linear foot. Each page here names its own trap and shows the working — the wall area, the pitch, the slope factor, the bay width — so the number can be checked with a tape before it is bought. Rooms are entered in feet or metres with one toggle; the arithmetic runs in one system throughout. Waste allowances ship with sensible editable defaults (10% flooring, 15% diagonal) instead of requiring you to know one. Nothing is uploaded, there is no sign-up, and the pages keep working offline once loaded — which is when a phone is most likely to be in a basement or a garden.
Related categories
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Generate graph paper, planners, charts, worksheets and flashcards you can print.
Frequently asked questions
Why is the paint estimate more gallons than area ÷ coverage?
Because the coverage on the can is for one coat, and almost every job is two. The calculator subtracts doors and windows at their standard areas, multiplies by the coat count you choose, and only then divides by coverage — the working is shown so each step can be checked against the room.
What waste percentage should I use?
The tools ship with 10% prefilled because that covers straight-lay cutting waste for most materials. Use 15% for diagonal or herringbone layouts, and more for fragile tile or patterned carpet where matching eats extra. The default is editable, not hidden — the number is a decision, and it is labelled as one.
Why does the tile calculator ask for grout width?
Tiles are laid on a pitch of tile plus one grout line in each direction, so the line is part of the count. On 12-inch tiles with a ⅛-inch line it adds about 2% — but on 2-inch mosaics the same line adds over 12%, which is exactly the order that otherwise runs short.
Are the stair and electrical-style results code-compliant?
The stair calculator checks the layout against the limits you enter — defaulting to the IRC residential values of a 7¾-inch maximum riser and a 10-inch minimum tread — and flags a non-compliant layout by name instead of accepting it. It is an educational estimate, not a substitute for your local code or an inspection; jurisdictions amend the model codes.
Why are the results rounded up?
A fraction of a gallon, roll, box, bag or yard cannot be bought, and rounding down leaves the job short. Every buy figure is a ceiling of the exact quantity, which is shown beside it so the rounding is visible and the ideal number is there when the supplier does sell fractions.