Tile Layout Calculator

Offset patterns shift alternate rows by one-third or one-half of the tile-plus-grout pitch. The table lists every clipped piece; counts do not assume that offcuts can be reused. Use actual tile dimensions, not the product’s nominal module. There is no single universal subway-tile size.

How to use it: enter your room dimensions, the tile size, and the grout gap between tiles, then choose a layout mode. "Start at edge" lines the first tile up flush with one wall, so every cut tile ends up along the opposite wall. "Centered" splits the leftover space evenly between both opposite walls, so the cut tiles at each edge match.

Subway describes a style, not a fixed size. For example, Marazzi Rice Blu is sold as nominal 3 × 8 inches while its listed actual dimensions are 2.95 × 7.87 inches. Use the measured or published actual product dimensions plus the separately specified joint.

Installation sequence: verify a suitable, sound and prepared substrate; dry-lay square reference lines and check edge cuts; choose the specified mortar and trowel; cut and set tiles while checking coverage and alignment; keep movement joints clear; grout and allow curing according to the product instructions. The calculator does not replace those product instructions.

Source: Daltile floor installation · Example: actual subway tile dimensions · Movement-joint guidance

Tile pitch is tile size plus grout gap. Count = ceil((room size + gap) / pitch), because there is no grout joint beyond the last tile. Centered alignment splits the excess equally between the two cut edges.

For a 3000 × 2400 mm room with 300 × 300 mm tiles and 3 mm grout, the grid is 10 × 8. Centered edge tiles are 286.5 mm wide and 289.5 mm high, for 80 tile pieces before waste.

Cut widths are the remaining pieces, not the amount removed. If an edge-start layout ends inside a grout joint, choose centered alignment. The schematic is shown for grids up to 2000 pieces.

The result above uses these exact values. This snapshot is included when the page is printed so the output can be checked against the original measurements.

Tile pattern

Straight grid

Room width

3000 mm

Room height

2400 mm

Tile width

300 mm

Tile height

300 mm

Grout gap

3 mm

Layout

Centered

Primary result: Grid: 10 x 8.

• Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
• Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
• When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.

Supports straight grids and alternating row offsets, not diagonal or herringbone layouts. The room must be rectangular without obstructions. Offset calculations are limited to 20,000 base-grid pieces. Deduct specified perimeter movement clearances from the covered dimensions before using this geometric plan.

A half-offset option is geometry only, not permission to use it with every tile. Large or bowed tiles may require a smaller manufacturer-approved offset to control lippage. Check the product’s actual sizes, permitted pattern and grout-joint specification before laying out.

The tile count is the exact number needed to cover the grid with no allowance for breakage, miscuts, or future repairs - add a waste margin (commonly 10% or more for diagonal or intricate patterns) when you actually order tile.

When the tile pitch divides the room size almost exactly, the reported edge cut can round down to 0.0 mm even though a small trim is still needed at the wall - always dry-lay the first row before cutting anything.