DIY Building Calculators & Material Estimators
91 free calculators, each purpose-built for one project. Enter your dimensions and get materials, hardware, a grouped shopping list, tools, cost and build time.
16 calculators
Decks & Structures
Size it, foot it, permit it — then price the material.
Decide these before you open a calculator — the decks & structures guide →
3 calculators
Fencing & Privacy
Divide the run into bays that land evenly, budget the concrete honestly, and pick a material you won't resent in ten years.
Decide these before you buy materials — the fencing & privacy guide →
14 calculators
Garden & Yard
Work out the cubic yards, the pounds of seed and the real cost before you order anything.
19 calculators
Concrete & Masonry
Cubic yards, slab thickness, base depth and reinforcement — and whether to pour it, lay pavers, or just spread gravel.
Settle these before you pick a calculator — the concrete & masonry guide →
39 calculators
Interior & Finishing
Six calculators for the inside of a room, plus the sequence and the waste rules that decide what you actually buy.
Sort this out before you pick a calculator — the interior & finishing guide →
How to use these
Pick the tool that matches the job, not the material
Every calculator here is built around one project type, because the quantity that actually decides your order changes with the job. A patio is priced by area, a fence by the linear foot with posts landing on their own spacing, a retaining wall by course height against the block you chose, and a roof by the square after a pitch factor stretches the plan area. A single general-purpose estimator has to flatten all of that into square footage, which is exactly where the numbers stop being useful at the store.
Start with the basic inputs — usually just dimensions and a material — and you get a complete plan immediately. Then open the advanced options to set spacing, base depth, footing depth, waste allowance and finishes, and watch the shopping list and cost move with them. That second pass is where the real value is: it turns the tool from a quantity lookup into a way to compare two ways of doing the job before you spend anything. If you are still deciding between approaches, each category guide above works through that choice first.
Answers
About these calculators
What does each calculator actually give me?
The same complete package every time: a quantity takeoff of materials and hardware with real stock sizes, that same list regrouped by store section so one trip covers the job, a required-versus-helpful tool checklist, a material cost range broken out by category, a realistic build time for your crew size, and the project-specific notes and code reminders that matter for that build. You can print the whole thing on one sheet or share the exact configuration as a link.
How accurate are the cost estimates?
They are material-only planning estimates built line by line from national-average retail prices, then shown as a range rather than a single false-precision figure. They exclude labor, delivery, tax, permit fees and tool rental. Your local prices, the grade you buy and the season will all move the number. Treat the range as a budgeting baseline and a way to sanity-check the material line on a contractor's bid, not as a quote. Every page shows when its figures were last reviewed.
Do I need to sign up, and is my data stored?
No sign-up, and nothing you enter leaves your browser. Every calculation runs client-side in the page, there is no server that sees your dimensions, and the site sets no cookies of its own. Your configuration lives in the page's URL, which is what makes a plan shareable and bookmarkable — send someone the link and they see exactly your numbers. There are no accounts to create and no project data held anywhere.
Are these plans code-compliant?
They are planning tools, not engineered drawings, and they will not substitute for your local building department. The structural figures use conservative published residential span and footing guidance, and the tools flag code-sensitive choices — joist span, footing depth below frost, guard height — when your inputs approach a limit. But codes vary by jurisdiction and amendments are local. Confirm spans, footings, setbacks and attachment details with your building department, and pull any required permits before you buy or build.