Label size calculator: millimetres, points and pixels
Type a label size once and get all four units back, at both print densities sellers actually run. The calculator also shows the scale a 4 × 6 page or an A4 two-up and four-up layout would apply to that size — the part a plain converter leaves out, and the part that decides whether a barcode scans.
Crop a Flipkart PDF4 × 6 thermal specFour labels per A4
Pick 4 × 6 in or type your own size
101.6 × 152.4 mm
| Measure | Your label |
|---|---|
| Millimetres | 101.60 × 152.40 mm |
| Inches | 4.00 × 6.00 in |
| Points (1/72 in) | 288.00 × 432.00 pt |
| Pixels at 203 DPI | 812 × 1218 px |
| Pixels at 300 DPI | 1200 × 1800 px |
| Where it prints | Page | Scale applied |
|---|---|---|
| Thermal · one label per 4 × 6 page | 288 × 432 pt | 86.8% — reduced |
| A4 · 4 labels per sheet | 595.28 × 841.89 pt | 91.9% — reduced |
| A4 · 2 labels per sheet | 595.28 × 841.89 pt | 91.9% — reduced |
| A3 at 100% | 842 × 1191 pt | 4 per sheet, 100% |
The three scale rows are one label per cell — untick “Keep invoice” on the crop tool, or each cell receives the whole A4 sheet instead. A3 is paper arithmetic: the workspace has no A3 layout.
A label is described in four units at once — millimetres on the box, inches in the marketplace template, points inside the PDF, pixels in the printer’s head — and sellers are usually handed two of them and left to guess the other two. The calculator above converts all four, then tells you what the 4 × 6 and A4 layouts would do to the size you typed, because a conversion that ignores the page is only half the answer.
The three formulas, so you can check any answer by hand
- Points: 1 in = 72 pt, so 4 in = 288 pt and 6 in = 432 pt. Points are what the PDF stores, and what a page-size dialog reports.
- Millimetres: 1 in = 25.4 mm, so 4 in = 101.6 mm and 6 in = 152.4 mm. A “100 × 150 mm” roll is a rounded name for the same stock.
- Pixels: px = inches × DPI, or px = points × DPI ÷ 72. At 203 DPI, 4 × 6 in is 812 × 1218 px; at 300 DPI it is 1200 × 1800 px.
| Size | Millimetres | Points | Pixels at 203 DPI | Pixels at 300 DPI |
|---|---|---|---|---|
| 4 × 6 in | 101.6 × 152.4 mm | 288 × 432 pt | 812 × 1218 px | 1200 × 1800 px |
| 100 × 150 mm | 100 × 150 mm | 283.5 × 425.2 pt | 799 × 1199 px | 1181 × 1772 px |
| Flipkart label block | 79.4 × 125.2 mm | 225 × 355 pt | 634 × 1001 px | 938 × 1479 px |
| A6 | 105 × 148 mm | 297.6 × 419.5 pt | 839 × 1183 px | 1240 × 1748 px |
That last row is the one that trips people up. “100 × 150 mm” and “4 × 6 in” are thrown around as if they were the same label, and on a thermal roll they nearly are — but a print dialog that snaps to a named paper size treats them as different pages. Convert the number on your stock, not the name on the listing.
How many fit: 4 × 6 roll, A4 four-up, A4 two-up, A3
A conversion on its own does not tell you whether the label will print at the size you converted. These are the cells the crop layouts actually give a label, and what a 225 × 355 pt Flipkart block becomes in each one:
| Layout | Cell for one label | 225 × 355 pt block prints at |
|---|---|---|
| 4 × 6 roll | 250 × 394 pt on a 288 × 432 pt page | 111.0% — 88.1 × 139.0 mm |
| A4 · 4 labels per sheet | 273.6 × 396.9 pt | 111.8% — 88.8 × 140.0 mm |
| A4 · 2 labels per sheet | 557.3 × 396.9 pt | 111.8% — 88.8 × 140.0 mm |
| A3, 100% (paper arithmetic) | 842 × 1191 pt of paper | 9 blocks at 100% |
A3 is the exception: it is the only size here that takes four true 4 × 6 labels at 100%, and the workspace has no A3 layout, so the count is paper arithmetic and you impose the pages yourself. The reason four labels cannot sit on A4 at their real size is the 300 mm problem, which has its own page.
203 vs 300 DPI: which sizes actually need the higher figure
203 DPI is 8.0 dots per millimetre and 300 DPI is 11.8. A thermal label printer with a 203 DPI head prints a 4 × 6 page as 812 × 1218 dots; the 300 DPI version prints 1200 × 1800. A Code 128 shipping barcode needs each bar or space to be a whole number of dots and at least one dot wide, and 203 DPI already gives it that at the label’s real size.
The higher figure earns its price on everything around the barcode: a 6.5 pt address line, a 2D code carrying more data, a SKU footer, a GST invoice shrunk onto the same sticker. If a label scans badly, resolution is rarely the cause — a page printed at 97% is. The 4 × 6 print spec explains what a 4 × 6 label prints at and why the scale, not the DPI, is the thing to check first.
Common sizes on Indian packing desks
| Name | Millimetres | Points | Pixels at 203 DPI | Pixels at 300 DPI |
|---|---|---|---|---|
| 4 × 6 in thermal | 101.6 × 152.4 mm | 288 × 432 pt | 812 × 1218 px | 1200 × 1800 px |
| 4 × 4 in thermal | 101.6 × 101.6 mm | 288 × 288 pt | 812 × 812 px | 1200 × 1200 px |
| 3 × 5 in courier | 76.2 × 127 mm | 216 × 360 pt | 609 × 1015 px | 900 × 1500 px |
| A6 stationery | 105 × 148 mm | 297.6 × 419.5 pt | 839 × 1183 px | 1240 × 1748 px |
The Flipkart block — 225 × 355 pt — is not on this list because it is not a stock size. It is the region this workspace measures on an A4 Flipkart sheet, and it is what the 4 × 6 and A4 layouts scale. If you are converting your own label, type its millimetres into the calculator and read the print scale underneath; that is the number that decides whether the barcode scans.
Printing the result: 100%, no scaling, paper size set to the label
A conversion is only worth the paper it prints on. Once you know the label is 288 × 432 pt, set the paper size to 4 × 6 in (or 100 × 150 mm), set scaling to 100% — “Actual size” in a browser, “None” in a Windows driver, no “Scale to Fit” on macOS — and leave “Fit to printable area” off. The page is already the paper size; any fitting only removes the dots the printer needed.
Then measure the first print. If the label is narrower than the number the calculator gave you, the dialog scaled it; if it is wider, you printed a layout that enlarges, such as the A4 four-up. How to print Flipkart labels covers the dialog names for each platform, and label printing cut off works through the faults in the order they happen.
Where to go next
Converted a size and want to crop to it: crop a Flipkart PDF. The destination side of a 4 × 6 roll: what a 4 × 6 label prints at. Why four labels do not fit an A4 sheet at full size: four labels on one A4 sheet. The measured Flipkart block in mm and pixels: Flipkart shipping label size.
Label size questions
How many pixels is a 4 × 6 label?
812 × 1218 px at 203 DPI and 1200 × 1800 px at 300 DPI. The PDF itself is vector and has no pixels — the figure is what the printer’s head rasterises at that density, which is why the same file measured on different printers gives different pixel counts.
Why is a 100 × 150 mm label not the same as a 4 × 6?
4 × 6 in is 101.6 × 152.4 mm, so the round metric label is 1.6 mm narrower and 2.4 mm shorter. At 203 DPI that is 799 × 1199 px instead of 812 × 1218 px. The 13-pixel difference is where a driver that snaps to the wrong paper size starts rescaling.
Do I need the pixel figure at all for a PDF label?
Only if you are placing the label in a raster template or asking a print shop for a specific file. A PDF label is vector, and its sharpness comes from the printer’s DPI, not from the file’s pixel count. Use the pixel row to compare stock and templates, not to “fix” a PDF.
How many labels fit on one A4 sheet?
Four, at 111.8% of the Flipkart block — 88.8 × 140.0 mm each. Two-up prints the same size on twice the paper. Four true 4 × 6 labels do not fit A4 at their real size: the best possible scale with no margins is 97.4%.
What size is a Flipkart label in pixels?
The measured block is 225 × 355 pt — 634 × 1001 px at 203 DPI, 938 × 1479 px at 300 DPI. The 4 × 6 layout prints it at 88.1 × 139.0 mm, which is 111% of that block, so the printed image is slightly larger than the source.
Does the calculator upload or store anything?
No. It converts numbers in the browser and has no file input. The crop tools are different: they need a signed-in account, process the PDF on our server, and the download link expires after 30 minutes.