Diamond Painting Canvas Calculator
Diamond painting covers a canvas with tiny resin drills placed on a regular grid. The number of drills is set by the canvas size and the drill dimension: divide the width and height by the drill size to get the columns and rows, then multiply. This calculator returns the column count, row count, total drills, and an estimated placing time from your own speed, and it lets you scale down for partial-drill designs by entering the coverage percentage.
Drill count formula
Columns = floor(canvas width in mm / drill size)
Rows = floor(canvas height in mm / drill size)
Total drills = columns * rows * coverage / 100
Estimated minutes = total drills / placing speed
Estimated hours = estimated minutes / 60
Canvas width and height in centimetres are converted to millimetres (times 10) and divided by the drill size to get whole columns and rows. Their product, scaled by the coverage fraction, is the total drills. Time follows from your placing speed.
Diamond painting context
- Drills are commonly 2.5 mm or 2.8 mm; use the size printed on your kit.
- Square drills sit flush; round drills are faster but leave small gaps.
- Full-drill canvases are covered edge to edge; partial-drill designs cover only part of the image.
- One centimetre equals ten millimetres, the basis of the unit conversion here.
- Bag counts per color vary by supplier and are not standardised; check your packaging.
Diamond painting: frequently asked questions
How many diamonds are on a canvas?
The drills sit on a grid. The number across equals canvas width divided by drill size, and the number down equals canvas height divided by drill size. Total drills is across times down. For a 30 by 40 cm canvas with 2.5 mm square drills, that is 120 columns by 160 rows, or 19,200 drills.
What is the difference between square and round drills?
Square drills sit flush with no gaps and give a crisp mosaic look; round drills are quicker to place but leave small gaps. Both are commonly 2.5 mm or 2.8 mm. The grid count uses the drill size you enter, so set it to your kit's stated size.
How long does a diamond painting take?
Time depends on your placement speed. Enter your drills-per-minute rate and the calculator multiplies total drills by the seconds per drill to estimate hours. At 20 drills per minute, a 19,200-drill canvas takes about 16 hours of placing.
Why is full drill different from partial drill?
A full-drill canvas is covered edge to edge with diamonds, so the grid count fills the whole area. A partial-drill canvas has diamonds on only part of the image, so multiply the full count by the fraction covered. Enter the coverage percentage to adjust the total.
How many diamonds come in a bag?
Bag counts vary by supplier; many list roughly 200 to 400 drills per color bag, but this is not a standard. Check your kit's packaging. This calculator reports total drills so you can compare against the counts your specific supplier prints on the bags.
Official sources
- National Institute of Standards and Technology: SI Units: Length.
- U.S. Department of Commerce, NIST: Metric (SI) Prefixes.
Reviewed by the CalculatorHub team, edited by James Graham, 16 June 2026. See our methodology.