Construction calculators

TEC Grout Calculator

Updated Sep 19, 2026 By Infinity Calculator
Rate Formulas
Unit System
Switching systems converts every entered value and every result. Results are always shown in both lb and kg.
Project & Tile Dimensions
Total installation area. Decimal point or comma both accepted.
Long side of a single tile.
Short side of a single tile.
Pick a preset or type an exact value — the two stay in sync.
Width of the grout line between two adjacent tiles.
Drives the headline result, packaging and footnotes. All products are still compared in the results tables.
Calculate from Room Dimensions (optional helper)
Joint Perspective Preview
Tile Grout joint
Joint Width: 1/8 in

Grout Coverage Results

Grout Needed (Selected Product)
 
Packages to Buy
 
Joint Area of Surface
 
Coverage Rate
 
Results include a recommended 10% waste buffer.
Display results as:
Standard Grouts
Calculated grout quantity for each standard grout product, including a 10 percent waste buffer
ProductQuantity NeededUnit
Ready-to-Use Grouts
Calculated grout quantity for each ready-to-use grout product, including a 10 percent waste buffer
ProductQuantity NeededUnit
Footnotes
Step-by-Step Solution
Material Required by Product
Grout Colorant Coverage Reference

Coverage per 8 oz bottle by tile size. The row matching your entered tile size is highlighted, and the last column is calculated from your project area.

Grout colorant coverage per 8 ounce bottle by tile size, with bottles required for the entered project area
Tile SizeCoverage per 8 oz BottleBottles for Your Area

Introduction

The TEC Grout Calculator tells you how much grout you need for your tile job. Enter your total area, your tile size, tile thickness, and how wide you want the grout lines. Then pick your TEC grout product.

You get your answer in pounds, kilograms, gallons, or liters. It also tells you how many bags or pails to buy, so you don't have to guess at the store. Every result adds a 10% waste buffer, because some grout is always lost during mixing and cleanup.

The calculator works in both imperial (inches and square feet) and metric (millimeters and square meters). Switch at any time and every number you entered converts with it. There is also a room size helper if you know your room length and width but not the total area.

Below your results you will see a step-by-step solution, a chart comparing all TEC grout products, and a grout colorant coverage chart. A small tile preview shows what your joint width will look like next to your tiles. You can print or save a summary of the whole job.

How to use our TEC Grout Calculator

Enter your tile size, your grout joint width, and the area you are tiling. The calculator shows how much TEC grout you need, how many bags or pails to buy, and a step-by-step breakdown with a 10% waste buffer added.

Unit System: Pick Imperial (inches and square feet) or Metric (millimeters and square meters). Every value you have already typed converts with it.

Total Area: Type the full area you will tile. Use square feet for Imperial or square meters for Metric.

Tile Length: Enter the long side of one tile.

Tile Width: Enter the short side of one tile.

Tile Thickness: Pick a common thickness from the list or type your own. Thicker tile means deeper joints and more grout.

Grout Joint Width: Pick or type the space between two tiles. It must be smaller than your tile length and width.

Select Grout Product: Choose your TEC grout, such as Power Grout, AccuColor EFX, Design FX, or Premium Grout RTU. This sets the bag or pail sizes and the notes shown.

Room Length and Room Width (optional): Enter room size, then click Apply to Area to fill in the total area for you.

Display results as: Switch between pounds/gallons and bags/pails to see the results the way you shop.

Click Calculate Grout Coverage to see your results. Use Print / Download Summary to save a copy, or Reset to start over.

What Is Grout and Why the Amount Matters

Grout is the material that fills the small gaps between tiles. Those gaps are called joints. Grout locks tiles in place, blocks water and dirt, and gives the floor or wall a clean, finished look. Buying too little grout means a trip back to the store and a color that may not match. Buying way too much wastes money.

What Changes How Much Grout You Need

Four things drive the number:

  • Tile size. Small tiles have more joints in the same space, so they use more grout. Large tiles use less.
  • Joint width. A wide joint holds more grout than a thin one. A 1/4 in joint can use about twice the grout of a 1/8 in joint.
  • Tile thickness. The joint is as deep as the tile is thick. Thicker tile means a deeper joint and more grout.
  • Total area. More square feet means more grout. Double the area and you double the grout.

How the Math Works

Picture one tile plus the grout that wraps around it. The full block is (tile length + joint) × (tile width + joint). Take away the tile itself, and what is left is grout. That leftover share, times the tile thickness, gives the space grout must fill. Multiply that space by the product's density to get weight in pounds or kilograms.

Grout Types

Sanded grout has fine sand in it and is used for joints about 1/8 in and wider. Unsanded grout is smooth and works best in thin joints, often on walls and soft tiles like polished marble that sand could scratch. Epoxy and specialty grout resists stains and chemicals, so it is common in kitchens and showers, but it must be mixed as a full kit. Ready-to-use grout comes already mixed in a pail. It saves time but is meant for walls and narrower joints.

Why Add 10% Extra

Real jobs are never perfect. Some grout sticks to the bucket, the float, and the sponge. Some joints end up a bit deeper than planned. Chipped tile edges eat more material. A 10% buffer covers that. Also buy full bags or pails from the same lot number, since color can shift a little between batches.

Tips Before You Buy

  • Measure the room and check your tile box for the true tile size, not the nominal size.
  • Rectangular tiles, like planks, have more joint length than squares of the same area.
  • Textured or rough tile pulls grout into its surface, so coverage drops.
  • Mix only what you can spread in about 30 minutes so it does not harden in the bucket.
  • Seal cement-based grout after it cures unless the product says sealing is not needed.

Formulas used

Joint fraction of tiled surface
f = \frac{(L+J)(W+J) - LW}{(L+J)(W+J)}
Base grout weight (lb)
G = f \times T \times A \times 144 \times D \times 0.0361273
Total grout with 10% waste buffer
G_{total} = G \times 1.10
Volume for gallon-rated products
V_{gal} = \frac{G_{total}}{\text{lb per gal}}
Bags or kits required
N_{bag} = \left\lceil \frac{G_{total}}{W_{bag}} \right\rceil
Pails required
N_{pail} = \left\lceil \frac{V_{gal}}{V_{pail}} \right\rceil
Coverage rate
R = \frac{G_{total}}{A}
Colorant bottles for project area
N_{bottles} = \left\lceil \frac{A}{C_{tile}} \right\rceil

Frequently asked questions

How many square feet does a 25 lb bag of grout cover?

It depends on tile size, joint width, and tile thickness. A 25 lb bag of cement grout covers roughly 350 to 400 sq ft of 12×12 in tile with 1/8 in joints. The same bag covers only about 150 sq ft of 4×4 in tile, because small tiles have far more joints in the same space.

How much grout do I need for a standard shower?

A typical 3 ft × 5 ft shower has about 100 sq ft of wall plus roughly 15 sq ft of floor. With 4×4 in tile and 1/8 in joints, that job needs about 17 to 20 lb of grout once you add a 10% waste buffer. That is one 25 lb bag or two 10 lb bags.

Can you use sanded grout in 1/16 inch joints?

No. The sand grains are too big to pack into a joint that thin, so the grout will crumble or leave voids. Use unsanded grout for joints under 1/8 in. Use sanded grout for joints 1/8 in and wider, where it resists shrinking and cracking.

How wide should grout lines be for 12x24 tile?

Most installers use 1/8 in to 3/16 in for 12×24 in tile. Large tiles are never perfectly flat, and a wider joint hides the small height change between tile edges. Going below 1/16 in leaves no room to adjust and makes lippage stand out.

How much water do you mix with a bag of grout?

Always follow the bag label, since every product is different. As a rough guide, cement grout takes about 1 quart of clean, cool water per 10 lb of powder. Extra water weakens the grout and can make the color turn out light or blotchy.

How long before you can walk on or shower over new grout?

Wait about 24 hours before light foot traffic and about 72 hours before water exposure like a shower. Cool or damp rooms slow curing, so give it longer. Heavy use too soon can crack joints or wash color out.

Does TEC Power Grout need to be sealed?

No. TEC Power Grout is made to resist stains and water on its own, so no sealer is needed. Most standard cement grouts do need a penetrating sealer after they cure, usually 48 to 72 hours later. Epoxy grouts also skip the sealer.

Can you use unsanded grout on a tile floor?

Only if the joints are very thin, about 1/16 in or less. Unsanded grout shrinks more, so in wider floor joints it cracks and pulls away from tile edges. For most floors with 1/8 in or wider joints, use sanded grout.

Can you mix two bags of grout together?

Yes, if you can spread it all within about 30 minutes before it stiffens. Check that both bags have the same color and lot number. Color can shift slightly between batches, and a mid-wall change will show once the grout dries.

How long does ready-to-use grout last once the pail is opened?

Seal the lid tight right after use and it usually stays good for several months. Skim off any dried crust on top before using it again. Once it stiffens into lumps, throw it out. Never add water to thin it, since that ruins the color and strength.

Why did my grout dry blotchy or in two different shades?

The most common cause is uneven water: too much mix water in one batch, or a wet sponge pulling color out during cleanup. Wiping too soon or letting haze sit also causes it. Mixing bags with different lot numbers can leave a clear color line.

Can you put new grout over old grout?

Not as a thin skim coat, it will flake off. You must grind or scrape out at least 2/3 of the joint depth, about 1/8 in minimum, then vacuum the dust and regrout. If the old grout is only stained, a grout colorant is an easier fix.

How many bottles of grout colorant do I need?

One 8 oz bottle covers about 350 sq ft of 12×12 in tile, but only about 125 sq ft of 4×4 in tile. Smaller tiles mean more joint length, so coverage drops fast. Divide your area by the coverage for your tile size and round up.