Pixels become physical centimetres only when you know the DPI: divide the pixel count by the DPI to get inches, then multiply by 2.54 to get centimetres. A 1080 × 1080 pixel Canva design, the default size for Instagram posts, comes out to roughly 28.6 × 28.6 cm at 96 DPI but only about 9.1 × 9.1 cm at 300 DPI — the same pixel value, the same image, two completely different print sizes. That single fact is why Canva users searching for a pixel-to-centimetre fix usually need a converter rather than a straight rule: the relationship between pixels and physical units is not fixed, it depends on the resolution you assume. The Pixels to CM Converter turns that DPI assumption into a concrete number you can type into Canva's custom-size dialog, so a pixel canvas and a cm canvas end up referencing the same physical size. The conversion itself takes one click once the DPI is set, which is the only variable you really need to think about.
Why Canva Users Need a Pixel-to-Centimetre Conversion
Canva works in pixels by default for most of its templates. Instagram posts, Facebook covers, LinkedIn banners, presentation headers, and most social-media design sizes are stored as px values. The moment you move into print, however, the conversation shifts to centimetres, millimetres, or inches, because printers and clients think in physical sizes. A 3.5 cm ID photo, a 21 × 29.7 cm A4 flyer, a 50 × 70 cm poster — none of these are described in pixels in everyday life. To bridge the two worlds, you need a reliable way to translate a pixel canvas into a centimetre dimension (or the reverse) without guessing.
The complication is that the conversion is not a single fixed ratio. The same 1920 × 1080 px canvas comes out to about 50.8 × 28.6 cm at 96 DPI, the reference value used by the CSS specification for screens, but only about 16.3 × 9.1 cm at 300 DPI, the standard for high-quality print. Mathematically, the path is straightforward: divide pixels by the DPI to get inches, then multiply by 2.54 to get centimetres (because one inch is defined as exactly 2.54 cm by the 1959 international inch). Open the Pixels to CM Converter and that calculation is done in one step, with the DPI you actually plan to use.
The Pixels-to-Centimetres Formula
The conversion is a two-step arithmetic once you route everything through inches. Step 1: inches = pixels ÷ DPI. Step 2: centimetres = inches × 2.54. To go the other direction — centimetres back to pixels — multiply the centimetre value by the DPI and divide by 2.54, or equivalently pixels = (cm × DPI) ÷ 2.54.
What "DPI" actually means in this context is the number of pixels packed into one linear inch of your output. On a screen, DPI is the CSS reference pixel density, defined as 1/96 of an inch, which is why 96 DPI is the de facto value for web and screen work. On a printed page, DPI is whatever density your printer resolves fine detail at — 300 DPI is the working number for photos, brochures, and anything that needs to look sharp at normal reading distance, while 72 DPI is a legacy value from early desktop publishing. The Pixels to CM Converter lets you type any of these values or any custom DPI in between, so the same tool handles both screen and print without a separate mode.
How to Switch Canva's Canvas from Pixels to Centimetres
Inside Canva, the unit change happens through the custom-size dialog. The Pixels to CM Converter is the calculation step that tells you what numbers to type in.
- In Canva, click "Create a design" in the top-right corner, then choose "Custom size" from the dropdown.
- Click the unit toggle next to the width and height fields — it defaults to "px", but you can switch it to "mm", "cm", or "in" with one click.
- Type the centimetre dimensions you want for your design. For an A4 print piece, type 21 in the width box and 29.7 in the height box with cm selected.
- If you already have a pixel dimension you want to keep and just need the cm equivalent, open the Pixels to CM Converter in another tab, type the pixel value, pick your DPI, and read the cm result from the results table.
- Type that cm value into the Canva custom-size dialog instead of the original px value, so the canvas physically matches your print or ID size.
One detail that often surprises people: once you set a design in cm, Canva still tracks the underlying pixel resolution internally based on its export DPI. A 10 × 10 cm canvas exported as a PNG comes out at roughly 1181 × 1181 px because Canva uses 300 DPI for print exports. That is why setting the size in cm first usually gives you a sharper print than starting in pixels and resizing later.
Choosing the Right DPI for Your Canva Design
DPI is the only knob that determines whether a pixel-to-centimetre conversion is "right" for your project. The Pixels to CM Converter exposes 72, 96, 150, and 300 as one-tap presets, plus a custom entry field, so the right number for the job is always in reach. The table below matches each preset to its typical Canva use case.
| DPI | Common use | When to pick it in Canva |
|---|---|---|
| 72 | Legacy web/digital graphics | Matching an old logo file, archive asset, or 1990s print layout. |
| 96 | Modern screens and CSS reference | Sizing something for a website, app, or social-media share. |
| 150 | Mid-range draft print | Previewing a flyer or poster before client sign-off. |
| 300 | High-quality print | Sending a final flyer, photo, ID card, or poster to print. |
Pixel counts scale linearly with DPI, so doubling the DPI doubles the px count for the same cm dimension. If your project sits between two presets — say, a 250 DPI mid-range print job — type a custom value into the converter rather than rounding to the nearest preset. The relationship between DPI and the cm size you end up with is described qualitatively in the table; the exact numbers, for any cm or pixel input, are what the converter gives you for free.
Real Canva Projects That Need Pixel-to-Cm Conversion
Below are four common Canva scenarios where a precise pixel-to-centimetre conversion makes the difference between a polished design and one that prints fuzzy or lands in the wrong physical size.
ID and passport photos
Many government photo specs are given purely in cm. A common 3.5 × 4.5 cm photo at 300 DPI calls for roughly 413 × 531 px. Setting the Canva custom size to 3.5 × 4.5 cm with the print preset forces the export to a sharp image at that resolution. If you already have a pixel-perfect photo in hand, the converter shows the cm size it will print at for a given DPI, so you can sanity-check the result before submitting.
A4 flyers and posters
A standard A4 page is 21 × 29.7 cm. At 300 DPI that is approximately 2480 × 3508 px, well above the canvas size of a typical Canva social-media template. Editing in pixel units and then "resizing" to fit A4 is what produces blurry, stretched-looking print files. Build the design at the correct cm size from the start, and the print comes out sharp.
Square Instagram posts sized for framed prints
Instagram's 1080 × 1080 px template is a fixed pixel canvas, but if the same image is to be printed as a 10 × 10 cm or 20 × 20 cm keepsake, the question is whether 1080 px is enough. At 300 DPI, 10 cm needs about 1181 px, so 1080 px is just under the safe threshold; at 150 DPI, 10 cm needs only about 591 px, so 1080 px is more than enough. The right DPI choice depends on how close the viewer will get to the framed print.
Web-to-print handoffs
Designers often start a Canva project as a website banner (1920 × 600 px) and later realise the client wants the same artwork as a cm-sized print piece. The Pixels to CM Converter lets them check the printed size of that pixel canvas before promising anything to the client, and it lets them size a new cm canvas to match the export resolution they need.
Working Backwards: From Centimetres to Pixels in Canva
Reading a cm value off the converter is the easy direction. The reverse direction — "I have a cm size, what pixel value should I set in Canva?" — comes up when you need to upload or set a custom size for a print-ready file. The arithmetic is the same formula rearranged: pixels = (cm × DPI) ÷ 2.54.
Worked example: suppose you need a 3.5 cm wide ID photo at 300 DPI. Pixels = 3.5 × 300 ÷ 2.54 = 1050 ÷ 2.54 ≈ 413. Round to 413 px and use that as the width in Canva's custom-size dialog (you can keep the unit in cm for the canvas itself; the export will still be 413 px wide at 300 DPI). The same calculation at 96 DPI gives 3.5 × 96 ÷ 2.54 ≈ 132 — far too few for a sharp print but plenty for a screen display.
DPI vs PPI: Which One to Use in Canva
DPI and PPI are technically different terms, though they are used interchangeably for sizing work. DPI (dots per inch) is a printing term, describing the ink dots a printer lays down on paper. PPI (pixels per inch) is a screen term, describing the pixels packed into a digital display. For converting a pixel canvas to a physical length, the two values are numerically the same, so the Pixels to CM Converter treats them as one input. When you see "300 DPI" on a Canva print preset, think of it as "300 effective pixels per inch of paper" — the printer and the screen agreed to use the same scale, so the math holds either way.