Paper sizes on Windows are easiest to set correctly when the physical sheet, the resolution, and the digital canvas agree: pixel width = width in inches × DPI, and pixel height = height in inches × DPI. The Paper Sizes Chart gives you a single reference for A-series, B-series, and US sizes, with dimensions in millimetres, centimetres, and inches, then converts a selected size to pixels at the resolution you choose. A Windows user can use it to settle the practical question before opening a document: use A4 or Letter, set the canvas to the right pixel dimensions, or prepare artwork for a printer. For example, A4 is 210 × 297 mm and US Letter is 215.9 × 279.4 mm; the two are close but not interchangeable, so a seemingly minor page-size choice can change margins or clip content. The chart runs locally in your browser, with no uploads and no sign-in. Use its reference table and converter together, then carry the same paper size and DPI decisions into your Windows app's print or export settings.
What Windows needs before you choose a paper size
A Windows print job has two size layers. The page setup describes the physical output—A4, US Letter, Legal, Tabloid, or another named sheet—while an image canvas describes the digital raster area in pixels. DPI connects them. A sheet does not have a permanent pixel count, so a familiar number labelled “A4 pixels” is incomplete unless the resolution is stated.
Start by checking what the printer is loaded with and what the Windows print dialog lists for the selected printer. Then use the chart to translate that physical choice into the units your design task needs. The A and B groups follow ISO 216, while Letter, Legal, and Tabloid use the ANSI and US conventions common in North America.
| Paper size | Standard group | Dimensions in millimetres | Dimensions in inches |
|---|---|---|---|
| A4 | ISO 216 | 210 × 297 | Approximately 8.27 × 11.69 |
| US Letter | ANSI/US | 215.9 × 279.4 | 8.5 × 11 |
| US Legal | ANSI/US | 215.9 × 355.6 | 8.5 × 14 |
| Tabloid, also called Ledger | ANSI/US | 279.4 × 431.8 | 11 × 17 |
Read each row as width × height in portrait. A4 is narrower and taller than Letter, while Letter is wider and shorter. That difference explains why a Letter document can shift margins or clip content when printed on A4. Keeping the physical and digital facts together makes it easier to check the tray label, page setup, and canvas against one reference instead of relying on visual similarity.
Choose the resolution that matches the destination
Use 300 DPI for high-quality print artwork and 72 DPI for screen output. A 150 DPI setting provides an intermediate pixel count when that is what the workflow calls for. In every case, DPI changes the number of pixels used to represent the paper; it does not change the physical length or width of the sheet.
| DPI | Typical destination | How to apply the result |
|---|---|---|
| 300 | High-quality print | Use for artwork that must retain detail at print resolution. |
| 150 | Intermediate raster | Creates a pixel count between lower and higher resolution settings. |
| 72 | Screen output | Provides the classic screen-resolution choice for digital assets. |
One worked example shows A4 width at 300 DPI: 210 ÷ 25.4 × 300 = 2,480 pixels. The converter applies the same method to A4's height and displays the complete result, 2,480 × 3,508 pixels. This creates a 300 DPI canvas for an A4 sheet without changing the sheet itself.
When a brief simply says “A4,” decide whether you need dimensions for an editable document, a raster image, or a screen layout. For an editable document, the page-size choice and printer setting are the main controls. For a raster image, the exact pixel width and height are essential. For screen use, enter the required screen resolution rather than assuming the print standard.
Set up a print-ready file from Windows
Use the chart alongside the print controls in your Windows application: the chart supplies dimensions, while the print dialog supplies printer-specific options and the final preview. Follow this sequence when a document or image must match A4, Letter, or another standard sheet.
- Confirm the physical sheet and orientation. Look at the paper package or printer tray, then open the application's Print or Page Setup area. Note whether the intended format is A4, Letter, Legal, Tabloid/Ledger, or another standard size. Decide between portrait and landscape before creating the canvas.
- Scan the reference table. In Paper Sizes Chart, move through the A series, B series, and US group. Find the exact format and read its width and height in millimetres, centimetres, and inches. Using the exact row prevents you from substituting a similar but different format.
- Load it in the converter. Choose the same paper size from the converter dropdown. Its exact dimensions then load into the working area, giving you one place to confirm the units before entering a resolution.
- Enter the required DPI. Type 300 for high-quality print, 72 for screen output, or another resolution required by your workflow. The pixel width and height update instantly, so there is no need to calculate each dimension separately.
- Create the document or image at the matching size. In a raster editor or design program, set the canvas to the pixel width and height shown by the converter. In a document or PDF application, choose the same named paper size and orientation in its page setup. Keep physical dimensions and pixel dimensions in their proper fields.
- Check scale, preview, and export. If the application offers scaling, use 100% or “actual size” when an exact reproduction matters. Inspect the print preview for margins, cropping, and fit-to-page changes. Export with the intended format selected, and confirm that the destination printer is loaded with the matching paper.
The key is consistency across three places: the paper in the tray, the page size selected in the application, and the pixel dimensions used for the artwork. This process works for editable pages, image layouts, and export files because each receives the measurement it actually requires.
Match the format to the paper in the tray
Paper-size names can look interchangeable until their dimensions are compared. ISO 216 defines the international A and B series, while North American workflows commonly use ANSI and US formats. A4 is 210 × 297 mm. Letter is 8.5 × 11 inches, or 215.9 × 279.4 mm. Letter is therefore a little wider and shorter, while A4 is a little narrower and taller.
- A series: ISO 216 sizes run from A0 down to A10, with each smaller size preserving the proportions of the series.
- B series: The ISO 216 B range begins with B0 at 1,000 × 1,414 mm and provides intermediate dimensions for formats such as posters, books, and envelopes.
- US group: Letter, Legal, and Tabloid are defined in inches, producing exact millimetre equivalents of 215.9 × 279.4, 215.9 × 355.6, and 279.4 × 431.8 mm.
- Unit conversion: One inch equals exactly 25.4 mm. Millimetres become inches by dividing by 25.4 and centimetres by dividing by 10.
Choose the format supported by the selected printer and then verify its dimensions. For portrait output, retain the chart's width × height order. Landscape changes the placement of those dimensions, so confirm orientation after making the change. Millimetres are especially useful for cutting and binding, while pixel results are more relevant to a screen canvas.
Avoid sizing errors before the final export
Most Windows sizing problems come from mixing a physical unit, a digital unit, and a printer choice. Check these points before exporting:
- Treating millimetres as pixels. A physical measurement has no fixed pixel count until a DPI is chosen.
- Assuming A4 and Letter are equivalent. Their different widths and heights can change margins, wrapping, and cropping.
- Using 72 DPI for a high-quality print job. Screen resolution and print resolution describe different output requirements.
- Forgetting orientation. Landscape output swaps how the width and height are arranged on the sheet.
- Selecting a scale that changes the result. A fit-to-page setting may alter the intended dimensions or placement.
- Rounding physical dimensions. Use the exact chart values rather than replacing 215.9 mm with 216 mm or similar estimates.
Increasing DPI does not enlarge the sheet; it increases the pixels used to represent the same physical area. Likewise, selecting a larger named format does not confirm that the printer can feed it. Check the supported media and loaded tray in Windows, use the chart for the dimensional conversion, and retain the intended size and DPI when creating variants.
Use the chart as a Windows preflight check
Before sending a job to a printer or publishing a screen asset, run through this final sequence:
- Confirm that the selected physical sheet matches the paper in the tray.
- Confirm that the application uses the same named page size.
- Confirm that the DPI matches the intended destination.
- Compare the artwork canvas with the converter's pixel width and height.
- Check orientation, scale, margins, and cropping in the preview.
This check supports document layouts, print images, cutting or binding files, and export dimensions for designers, print buyers, students, and developers. Paper Sizes Chart keeps the lookup and live DPI conversion together and runs locally in your browser, so no document or image needs to be uploaded and no account is required. It provides the dimensions; the Windows application completes the print workflow.
For a deeper look, see Edit PDF Metadata on Windows: Fields, Dates, and Checks.