Epoxy floor coating calculator

The path is pure arithmetic with no network, model or filesystem side effects, so the same JSON pins cleanly in automated tests.

Measure floor area and match kit coverage to thickness and units

Express the result as floor_area in square feet, square metres or any other square unit you prefer—the calculator never converts units, so the coverage printed on the epoxy kit for your planned thickness must use the same square system. Optional aliases area, room_area, surface_area, garage_area and basement_area are accepted for floor_area; coverage, coverage_per_kit, kit_area and sq_per_kit map to kit_coverage. Both geometric inputs must be strictly positive finite numbers: zero, negative or non-numeric values raise invalid_input and are not charged. Extremely small or huge values outside the published stability range are also rejected so floating-point results stay meaningful on a Worker isolate.

Waste, coats, and how the ceil math turns area into whole kits

Real epoxy installs always need a little extra material. Vertical cove bases and wall returns consume product that never appears on the plan view area, cold or porous concrete drinks the first pass, roller edges and bucket walls leave residue, and a partial kit opened for touch-ups is hard to re-use after pot life expires. Ten percent suits a simple sealed rectangular garage with one coat; raise it to twelve or fifteen for rough, highly absorbent slabs, heavy flake broadcast systems that bury more resin, or rooms with many posts and recesses; lower it toward five for experienced crews on dense, previously sealed floors with clean geometry. The optional waste_percent field defaults to ten when omitted and accepts values from zero through one hundred; aliases waste, waste_allowance, overage and extra_percent map to the same number. The optional coats field defaults to one and accepts whole integers from one through twenty for multi-coat base-plus-build systems that use the same coverage per coat; aliases num_coats, layers and coats_count are accepted. The engine multiplies floor_area by coats to get coated_area, builds waste_factor as one plus waste_percent divided by one hundred, multiplies to get area_with_waste, then divides by kit_coverage. That quotient is kits_exact; kits_needed is the ceiling of that quotient so a fractional remainder always becomes one more full kit on the order sheet. kits_per_coat_exact shows the waste-adjusted single-coat demand, leftover_coverage_in_last_kit shows unused square coverage in the final kit, and method is always area_coats_waste_ceil_kits for stable downstream branching. Negative waste, fractional coats, missing required fields and non-positive floor area fail with invalid_input. Identical inputs always produce identical JSON because the path is pure arithmetic with no network, random seed or wall clock.

API usage, pricing, epoxy workflows, and practical limits

Call the free in-browser epoxy floor coating calculator for quick DIY estimates, garage makeovers, contractor whiteboards and showroom counters without building a spreadsheet. The capability does not schedule pot life, ambient temperature windows or moisture testing; those remain process checks outside the arithmetic contract. Send a JSON body with floor_area and kit_coverage, plus optional waste_percent and coats when the defaults are not appropriate for your slab or product line. Use the prepaid API when a home-improvement app, flooring ecommerce configurator, quantity-takeoff pipeline or property-management tool needs a stable contract under KIT balance at $0.002 per successful item; validation failures never consume balance after the engine rejects the request. Pair this endpoint with unit converters when customers mix imperial and metric packaging, or with room helpers when length and width arrive as separate fields that you multiply client-side before calling. Primers, decorative flake packs, polyaspartic topcoats and crack-fill cartridges often have their own coverage numbers—run a second call with each product’s kit_coverage rather than forcing one label to represent the whole system. Authors shipping SDKs can map kits_needed straight into cart lines while showing area_with_waste, kits_exact and leftover_coverage_in_last_kit as explanatory detail for the buyer or estimator.