Tile project cost estimator

The same pure function powers the free browser tool and the paid API, so a phone check in the showroom matches the line item a script posts later. Non-positive area and negative prices or waste are rejected with invalid_input instead of a silent nonsense total. Successful API calls use the published base of $0.002 per item; validation failures are not charged.

How the tile project cost formula works

Start from the materials identity used on every retail and contractor take-off for ceramic, porcelain, natural stone, and mosaic work: tile material cost is the coverage you must buy times the unit price of the tile, plus the adhesive and grout you will open for that job. Tile price, thinset cost, grout cost, and waste percent must be non-negative so a zero-waste perfect rectangle and a free leftover bag remain expressible without inventing negative money. Write waste_factor equals one plus waste_percent divided by one hundred, so ten percent waste means you plan for one hundred ten percent of the bare tiled area. Multiply bare area by that factor to obtain area_with_waste—the effective tile coverage target after cuts around cabinets, niches, diagonals, broken pieces, and shade-lot extras. Multiply area_with_waste by tile_price to produce tile_cost in the same currency as the unit price. Add thinset_cost and grout_cost as project totals (bags times bag price, or a supplier lump sum) without re-applying the waste factor, because bag purchases for thinset and grout usually already include their own rounding and a second waste pass would double-count allowance. The response also echoes waste_area, materials_total, and cost_per_area so you can audit the math against a hand calculation on the packing slip and compare jobs of different sizes on a per-square-unit basis. The pipeline is deterministic floating-point arithmetic with no random seeds, no wall-clock timestamps, and no network calls, so identical inputs always produce identical JSON. Area must be strictly positive: zero or negative surface is rejected with invalid_input because coverage would be non-physical.

What you send and what you get back

All five fields are required. Send five finite numbers: area for the bare tiled surface in square units, tile_price for the unit price of tile per matching square unit, thinset_cost for the adhesive materials total, grout_cost for the joint materials total, and waste_percent as the extra tile percentage (for example ten for a ten percent cutting allowance). Aliases such as surface, sqm, price_per_area, adhesive_cost, joint_cost, and waste_pct are accepted so forms and query strings can reuse the same contract. Missing fields, non-numeric strings, NaN, and Infinity fail with invalid_input and are not charged. When area is zero or negative the request fails with a message that area must be positive, so clients can correct dimensions before retrying instead of receiving a zero or negative total. When any cost or waste field is negative the request fails naming that field. On success the response echoes cleaned inputs, waste_factor, waste_area, area_with_waste, tile_cost, materials_total, cost_per_area (materials_total divided by bare area), a unit_note reminder to keep one area and price system, and a short formula string for documentation. Classic checks include a twenty square-metre room at twenty-eight point five currency units per square metre, ten percent waste, forty-five for thinset, and thirty-two for grout: area with waste is twenty-two, tile cost is six hundred twenty-seven, and materials total is seven hundred four. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.

Where tile project cost estimates show up in real work

Homeowners renovating kitchens, bathrooms, and laundry rooms need a trustworthy materials total before they buy large-format porcelain with a high unit price and a long lead time, especially when thinset and grout are easy to forget at the counter. Flooring and tile contractors build room schedules from measured areas and supplier unit prices; a single deterministic endpoint that inflates only the tile line reduces spreadsheet drift between the estimator and the purchasing clerk. Interior designers comparing three tile SKUs for the same plan can swap only tile_price while holding area, waste, thinset, and grout fixed, then rank materials_total and cost_per_area without re-deriving the waste math each time. Property managers planning multi-unit refreshes feed a batch of room areas and SKU prices through the API and attach materials_total to purchase orders so overstock stays intentional rather than accidental. Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance. If you later need tile piece counts, wall openings, or geometric grout kilograms, treat those as separate search intents and landings—home.floor_tiles, home.wall_tiles, and home.tile_grout—rather than overloading this materials-cost page with layout geometry.