Tile Layout Calculator

About this calculator

Model straight or 50% brick tile layouts with grout, edge pieces and rotation. Compare tile counts, selected extra, boxes and entered-price costs.

How to measure the room and tile

Measure the width and length of one rectangular surface. This tile calculator does not subtract cabinets, doorways or obstacles, join rooms, or adjust for walls that are not square. Enter tile face width and length separately from the grout joint. Use dimensions appropriate to your material rather than assuming its nominal label is an exact measurement.

Room, tile and grout units can be set independently to meters, centimeters, millimeters, decimal feet or decimal inches. Switching units converts accepted values and retains calculation precision; fix incomplete dimensions before converting. Fractions such as 1/8 are not accepted: enter 0.125 inches instead. Accepted edits recalculate instantly. Announce estimate reads the result or focuses the invalid field.

Geometry methodology and grout convention

The room is the rectangle from (0, 0) to (room width, room length). A tile is an axis-aligned rectangle. Its horizontal repeating module is oriented tile width + grout width; its vertical module is oriented tile length + grout width. Grout is the space between tile faces, not added tile area.

The engine clips each candidate tile to the room. A positive-area intersection counts as one modeled tile unit. Merely touching the room with a line or point does not count. Numerical comparisons use 32 machine epsilons multiplied by the largest room/tile dimension or one meter; only machine-scale overlaps are ignored. Geometry is not rounded to displayed dimensions.

No exterior grout band or perimeter expansion gap is added or deducted. Edge aligned places a tile corner at the room corner. Centered grids are clipped as they lie, so a room edge can fall within a grout band; the edge-piece report then says no tile touches that edge. This convention is not an installation joint specification.

Straight and 50% brick patterns

Straight keeps all tile rows aligned. Brick shifts alternate rows horizontally by half the repeating horizontal module: (oriented tile width + grout) ÷ 2. This is a real offset grid, not a waste multiplier. Row zero is the row anchored by the selected start; odd positive and negative row indices are shifted.

The offset includes half a grout joint. First and last tiles can be partial, and opposing edge widths can differ between alternating rows. A 50% offset here is a mathematical pattern choice, not a statement that it suits a particular tile or installation. Diagonal and other angled patterns are not supported in this version.

Centering, starting positions and tile rotation

Edge aligned uses origin zero on both axes. Centered tile puts an anchor tile center at the room center: origin = (room dimension − oriented tile dimension) ÷ 2. Centered grout puts a grout-joint center at the room center: the first tile after it starts at room dimension ÷ 2 + grout ÷ 2. With zero grout this is a tile seam.

These anchors repeat in both directions before clipping. In brick mode, alternating row shifts still apply, so centering does not promise equal edge pieces in every row. Orientation A uses entered tile width across the room width; B swaps tile width and length. Rotation leaves the room unchanged and brick rows horizontal. It does not rotate the entire room or the row direction.

All six start/orientation alternatives run through the same engine. Compare layout count, cuts and actual edge dimensions; no option is called best, correct or recommended. Changing the selected extra does not change any tile geometry.

Boundary-cut tiles and edge pieces

A boundary-cut tile intersects the room but does not fit completely inside it. Each such tile counts once, even if two room edges cut it. A full tile exactly touching an edge is not a cut. A tile larger than the room may represent one tile cut on several sides.

Left/right values are the widths of clipped tile rectangles touching those edges; top/bottom values are their heights. Brick can produce a range. No tile at an edge means the edge lies in modeled grout. The smallest boundary-piece side is the minimum width or height among cut rectangles. It is not a minimum usable cut or a safety threshold.

The boundary-cut count is a geometric indicator, not an optimized cutting plan. Each intersecting position consumes a separate modeled tile unit; no perfect offcut reuse, kerf, breakage, tool capability or installer feasibility is inferred.

Extra allowance, whole boxes and entered-price cost

Tiles to purchase = ceil(modeled layout tiles × (1 + selected extra percent ÷ 100)). Choose 0%, 5%, 10%, 15% or a custom value up to 100%. The default 10% is an editable example, not a universal recommendation. Only machine-level noise near a whole number is snapped before ceiling.

Optional tiles per box must be a positive whole number. Boxes = ceil(tiles to purchase ÷ tiles per box). Whole-box purchased tiles = boxes × tiles per box. For example, 186 required tiles with 20 per box require 10 boxes, containing 200 tiles. The calculator never rounds boxes downward.

Tile-price mode multiplies tiles to purchase by the entered price per tile. Box-price mode multiplies whole boxes by the entered price per box and requires tiles per box. If boxes are entered in tile-price mode, extra tiles in rounded boxes are not added to tile-price cost; use box-price mode to model that purchase basis. Blank price omits cost; zero is an explicit zero price. Changing price mode clears the previous price.

Prices are in USD, with no exchange-rate conversion, retailer data or live pricing. Costs exclude tax, delivery, labor, adhesives, grout and other installation materials. Room area includes grout spaces; purchased tile count × nominal tile area is not a claim of room coverage.

Worked example and Reset defaults

The default is a 4 m wide × 3 m long room, 600 × 300 mm tiles, 3 mm grout, Straight, orientation A, Edge aligned, and 10% selected extra. Boxes and price start blank.

The modules are 603 × 303 mm. Seven tile columns intersect ten rows, giving 70 modeled layout tiles and 16 boundary-cut tiles. The right piece is 382 mm wide and the bottom piece is 273 mm high. Ceiling of 70 × 1.10 gives 77 tiles to purchase. Room area is 12 m².

Reset restores those dimensions, units, pattern, orientation and start, clears box and pricing values, removes copy feedback and validation errors, and returns focus to room width.

Preview, assumptions and limitations

The responsive SVG renders the exact clipped rectangles counted by the engine. It shows room bounds, tile faces and grout spacing; outlines are display strokes. It is a geometric planning illustration, not a scaled construction drawing or optimized cutting plan. Numerical edge dimensions and counts provide a textual equivalent.

Individual rectangles are shown only for layouts up to 600 modeled tiles. Above that threshold, a clear message replaces the SVG while exact numerical geometry remains available. Each layout is limited to 20,000 candidate positions before intersection work begins; this conservative bound includes a small number of outside positions. Exceeding it pauses that layout rather than approximating its count. An oversized alternative can be unavailable while the selected layout remains valid.

Canonical lengths are meters. Room sides accept 0.1–100 m; tile sides 0.01–5 m; grout 0–0.05 m; extra 0–100%; boxes 1–10,000 tiles; and prices 0–1,000,000 USD. These are computational limits, not construction requirements. Malformed numbers, nonfinite values and unsupported patterns fail validation. Display rounding never feeds back into geometry.

This calculator does not determine substrate suitability, waterproofing, movement/control joints, expansion gaps, layout around obstacles, doorways/cabinets/fixtures, wall squareness, tile calibration/variation, installer cut feasibility, offcut reuse, adhesive/grout quantity, installation standards or building-code compliance. It provides no installation approval.

Copy, Print and privacy

Copy Estimate creates a plain-text summary of accepted dimensions, pattern, orientation, start, counts, selected extra, active boxes/prices and limitations. It omits raw inputs and geometry arrays. Unavailable clipboard access exposes a labeled selectable manual-copy field and status message.

Print Estimate uses the browser print dialog for the primary result, preview where available, comparisons, calculation details and limitations. No PDF service is used. All calculations stay in tab memory: no Share, URL state, storage, analytics or calculation networking. Copy and Print occur only through explicit actions.

Tile Layout Calculator FAQ

How many tiles do I need?

Enter room, tile and grout dimensions, then choose a pattern and start. The engine counts tile positions intersecting the room and applies your selected extra to that count. It does not use room area divided by nominal tile area as the final layout quantity.

Does grout spacing affect tile layout?

Yes. Grout changes both repeating modules, so it can change tile positions, edge pieces and counts. No exterior joint is assumed, and the calculator does not estimate grout material.

What is the difference between layout tiles and purchase tiles?

Layout tiles count intersecting tile units, including boundary-cut units. Purchase tiles add your chosen percentage and round upward. Whole boxes may contain additional tiles beyond that purchase requirement.

How does the selected extra allowance work?

It multiplies the layout count by 1 + extra/100 before rounding upward. It leaves the layout and preview unchanged. Ten percent is an example, not a recommended allowance for every project.

How does a straight layout work?

Rows and columns share aligned tile edges, separated by the entered grout width. Edge aligned starts a tile at the room corner; centered modes shift the repeating grid before clipping it to the room.

How does the 50% brick offset work?

Odd-indexed rows shift by half of tile width plus grout, measured in the selected orientation. Even rows keep the anchor position. The engine clips both row types independently, including their first and last partial tiles.

How do I convert the estimate to tile boxes?

Enter the number of tiles in one box. The required boxes round purchaseTiles/tilesPerBox upward, and the result also shows the actual whole-box tile count. Price per box uses that box count; price per tile uses the extra-adjusted tile requirement.

What does rotating the tile change?

Orientation B swaps tile width and length in the same room. It can change row count, edge pieces, cuts, purchase tiles, boxes and cost. It does not change tile area, room dimensions or the direction of brick rows.

What does the boundary-cut tile count mean?

It counts tiles that overlap the room but extend past at least one edge. A corner-cut tile still counts once. The indicator does not count individual saw cuts, optimize offcuts or prove that a narrow piece can be installed.

Is the preview an exact installation or cutting plan?

No. It shows the modeled rectangular intersections only. It excludes obstacles, out-of-square walls, expansion gaps, tile variation and cut feasibility. Diagonal layouts are not supported, and large layouts retain numerical results with an explicit preview-limit message.

Sources and model review

Reviewed September 27, 2026 for geometry, arithmetic and unit conversion, not installation or professional design approval. NIST: SI units and length (opens in a new tab) supports metric length and area relationships; NIST: conversion factors (opens in a new tab) supports the international foot conversion. This model uses 1 ft = 0.3048 m and 1 in = 0.0254 m.

Pattern anchoring, the perimeter convention, extra allowance and bounds are explicitly stated project choices. These sources do not endorse the calculator, a layout or an installation method.