How to use the Procreate Brush Size Converter
- Give the brush a real number. Open Calibrate from a test stroke, enter the width you measured and the slider percentage you drew it at, then press Use as maximum size. If you just want to convert units, skip this and type a maximum you already know into Brush maximum size.
- Describe the canvas. Pick a preset under Canvas or type the Width, Height and DPI from Procreate’s Actions → Canvas → Canvas information.
- Set the size any way you like. Drag the Size slider, or type into any of the five boxes: percent, pixels, millimeters, inches or points. The rest update instantly, and the preview redraws the stroke to scale on your canvas.
- Plan a canvas change. Enter the new width under Same look on a canvas this wide. The three thumbnails show the stroke on the old canvas, the same percentage on the new one, and the corrected percentage. Move to new canvas makes the new size your working canvas.
- Press Copy results to paste the numbers into your brush notes or a client spec.
Why the same brush looks thinner on a bigger canvas
Procreate measures strokes in canvas pixels, not in screen pixels or in fractions of the artwork. A stroke that is 30 px wide stays 30 px wide whether the canvas is 2048 px or 8192 px across. What changes is how much of the picture it covers: 30 px is 1.46% of a 2048 px canvas but only 0.73% of a 4096 px one.
You feel the difference the moment you pinch to fit the whole picture on screen. A 4096 × 4096 canvas fitted to the 2048 px height of a 12.9-inch iPad Pro is shown at 50%, so that 30 px line occupies 15 screen pixels. The same line on a 2048 canvas is drawn at 100% and looks twice as heavy. How wide a screen pixel is in turn depends on the display’s density, which the Screen Resolution & PPI Calculator works out. Many brush makers tune their sets on screen-size canvases, which is why imported brushes can feel like fineliners on a large print file.
The size slider adds a second layer of indirection. Its percentage is a share of the brush’s own maximum, set in Brush Studio, so 25% on a gouache brush and 25% on a technical pen are unrelated widths. Converting both to pixels is the only way to compare them, match them, or reproduce a line weight in Photoshop, where the brush Size field is already in pixels (from 1 to 5,000 px).
DPI is the third variable, and it never touches the pixel count. It only decides how big each pixel prints. A 30 px stroke is 2.54 mm wide at 300 DPI, 5.08 mm at 150 DPI and 10.58 mm at 72 DPI.
What Procreate shows, and what it keeps to itself
| Setting | Where it lives | Unit you see |
|---|---|---|
| Brush size | Left sidebar slider | Percent of the brush’s range |
| Maximum and Minimum size | Brush Studio → Properties → Brush behavior | Relative slider, not pixels |
| Canvas width, height, DPI | Actions → Canvas → Canvas information | Pixels and DPI |
| Grid size | Actions → Canvas → Edit Drawing Guide | Pixels — handy as a ruler |
| Photoshop brush Size | Options bar or right-click on canvas | Pixels |
Because only the canvas and the drawing guide speak in pixels, the drawing guide is your measuring tape. Set a 10 px 2D grid, draw a firm, straight stroke at a known percentage and count squares across its widest point. Pressure matters: many brushes link Apple Pencil pressure to size, so a light touch measures thin. Also, the converter assumes the slider scales width in a straight line from 0 to the maximum. Procreate doesn’t document its slider curve, so if a size matters, test one stroke at the exact percentage you plan to use.
Matching one stroke across canvas sizes
Here is one brush with a measured 120 px maximum, set to 25% (30 px) on a 2048 px square, carried to larger canvases with the same look:
| New canvas width | 30 px covers | Pixels needed | Slider setting |
|---|---|---|---|
| 2048 px | 1.46% | 30 px | 25% |
| 2732 px | 1.10% | 40 px | 33.3% |
| 3000 px | 1.00% | 43.9 px | 36.6% |
| 4096 px | 0.73% | 60 px | 50% |
| 6000 px | 0.50% | 87.9 px | 73.2% |
| 8192 px | 0.37% | 120 px | 100% |
At 8192 px this brush has nothing left to give. Anything wider means duplicating it and raising Maximum size in Brush Studio, then measuring again.
Tips from practice
Write the maximum into the brush name. Duplicate your inking brush and rename it something like “Ink — 120 px max”. Six months later you will not remember the calibration, and the name travels with exported .brushset files.
Pick the canvas before you ink. Resizing a canvas later through Crop & Resize resamples every stroke, so line weights scale with the picture and fine hatching softens. Settle the print size first with the Digital Canvas Size for Print calculator, then choose brush sizes for that canvas.
Think in points for print linework. Many print shops treat roughly 0.25 pt as the thinnest line that reliably reproduces. At 300 DPI that is about 1 px, so a 3–4 px pen (0.7–1 pt) is a safer floor for comics and line art that will be printed small.
Match brushes between apps through pixels. When you move a piece from Procreate to Photoshop for finishing, convert your Procreate percentage here and type the pixel value into Photoshop’s Size field. The [ and ] keys then nudge the size from a known starting point instead of a guess.
Keep test strokes on a hidden layer. A small swatch of each calibrated brush at 10%, 25% and 50% on a hidden layer gives you a visual ruler inside the file. It also reveals at a glance whether a brush’s Minimum size is lifting the low end of the slider.