TryBuildCalc

Tile Grout Calculator (Tile Grout Bags & Cost)

Calculate grout for a 100 sq ft tiled area with standard floor tile.

Inputs

Section 1: Tiled Area & Tile Size

ℹ️Known-area mode is quickest if you already have the tiled area. Use room dimensions if you'd rather enter length and width directly.

Multiple Areas (e.g. Floor + Wall)?

ℹ️Use total floor or wall tile area. Room dimensions are not required.

Common tile sizes

Section 2: Grout Joint

ℹ️Typical grout joints are 2-5 mm for standard floor and wall tile.

ℹ️Usually close to tile thickness, unless the joint is only partially filled.

Section 3: Grout Type & Wastage

ℹ️Auto-fills a typical density and wastage for the selected type — both remain editable, and Custom leaves them fully manual.

ℹ️kg/m³. Check the product datasheet for the most accurate figure.

ℹ️8% for unsanded cement grout, 10% for sanded cement grout, 15% for epoxy or textured tile.

Section 4: Bags

Section 5: Cost

Enable Cost Estimation?

Recommended grout: 1.31 kg (1 bags)

Tiled area: 9.29 m²

Grout Volume & Weight

Tiled Area: 9.29 m²

Grout Volume: 0.74 litres (0.0007 m³)

Grout Weight (before wastage): 1.19 kg

Wastage Added: 0.12 kg

Final Grout Required: 1.31 kg

Bags & Coverage

Bags Required: 1 bags

Coverage per Bag: 39.06 m²

Quick Insight

Buy at least 1 bags from the same production batch.

Calculated from tiled area, tile size, and grout joint dimensions.

Assumptions Used

Grout volume from joint width, joint depth, and tile size | Bag count rounded up to the next whole bag | Colour-matched bags should come from the same production batch.

Bill of Materials

Main material: 1 bags + recommended tools

+

Computed items reflect your entered area and joint dimensions; consumables below are general recommendations — actual needs vary by product and site.

For Your Job

Grout

1 bags

1.31 kg total

General Tools & Consumables

Grout float (rubber)

tool

Bucket & sponge

consumable

Mixing paddle & drill

tool

Grout sealer

site-dependent

Approximate results for planning only. Verify with a professional.

Grout Joint SectionTileTileJoint width: 3 mmJoint depth: 8 mmTile length: 600 mmTile width used with tile length to estimate joint volumeTile width: 600 mmDiagram simplified for clarity (not to scale)

Looking for the verification checklist, reference tables, or tips and mistakes?See the complete Grout Calculator.

Tile grout calculation

This page starts with 100 sq ft (about 9.29 m²) of tiled area at 600x600mm — that's about 1.19 kg of grout, still just 1 bag at 5 kg after 10% wastage.

100 sq ft is a frequently searched reference size — change the area or tile size below if your actual job differs.

  • Area: 100 sq ft.
  • Tile: 600 x 600 mm.
  • Bag size: 5 kg.

How grout quantity is calculated

The calculation uses the tiled area and the approximate volume of grout joints created by the tile grid. Wider joints, deeper joints, and smaller tiles all increase grout quantity.

Step 1 - Calculate grout volume

Area = Room Length x Room Width, or entered known area

Volume = Area x Joint Width x Joint Depth x (Tile Length + Tile Width) / (Tile Length x Tile Width x 1000)

Multiple Areas = Sum of every area's volume above, combined into one total

Calculation Mode lets you enter tiled area directly or let the calculator work it out from room length and width — both feed the same volume formula. Each tile contributes one joint-width strip along its length and one along its width, so smaller tiles create proportionally more joint volume per m² than larger ones. Switching on Multiple Areas lets you combine floor, wall, or several rooms with different tile sizes, joint dimensions, and grout products in one run.

Step 2 - Convert volume to weight

Grout Weight = Grout Volume x Grout Density

Selecting a Grout Type auto-fills a typical density (around 1600-1650 kg/m³ for cement-based, 1750 kg/m³ for epoxy) — always editable, and best replaced with the exact figure from your product's datasheet when available.

Step 3 - Add wastage and calculate bags

Final Grout = Grout Weight x (1 + Wastage / 100)

Bags = ROUND UP(Final Grout / Bag Size)

Wastage covers mixing residue, tooling loss, and colour-match test patches — auto-suggested from Grout Type (8% unsanded, 10% sanded, 15% epoxy) and always overridable. Bag count is rounded up because grout is purchased in full bags.

Step 4 - Calculate cost

Cost = Bags x Price per Bag

Cost only appears when Enable Cost Estimation is switched on and a price per bag is entered, shown in your selected currency.

Real-World Grout Calculation Example

This example uses the active inputs above and follows the same steps from the formula section.

Input Values Used

InputValue
Tiled area100 sqft
Tile size600 mm × 600 mm
Joint width / depth3 mm / 8 mm
Grout typeCement — Sanded (joints 3-12mm)
Density1600 kg/m³
Wastage10%
Bag size5 kg

Step 1 — Grout Volume

CalculationFormula / SubstitutionResult
Grout volume9.29 m² × 3 mm × 8 mm × (600 + 600) / (600 × 600 × 1000)0.0007 m³ (0.74 L)

Step 2 — Grout Weight

CalculationFormula / SubstitutionResult
Grout weight0.0007 m³ × 1600 kg/m³1.19 kg

Step 3 — Wastage and Bags

CalculationFormula / SubstitutionResult
Wastage1.19 kg × 10%0.12 kg
Final grout requiredWeight + wastage1.31 kg
Bags requiredROUND UP(1.31 / 5 kg)1 bags

Therefore, for this 9.29 m² job you need 1.31 kg of grout, or 1 bags.

This page keeps things focused on the calculation above. For the full construction guide — verification checklist, reference tables, usage steps, tips, common mistakes, and limitations.See the complete Grout Calculator.

Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.

FAQ

This calculator uses the same volume formula tile professionals use — area x joint width x joint depth x (tile length + tile width) / tile area — which is far more accurate than a flat percentage guess, but the exact result still depends on the actual product's density, which varies by manufacturer.
Use the nominal size printed on the tile box (e.g. 600x600mm); actual tile size is usually within 1-2mm of nominal for rectified tile, which has negligible effect on the grout estimate.