Change the DPI of an Image
Change print DPI losslessly
Only PNG and JPEG store a DPI tag. GIF, WEBP and SVG have no field for it. Drop several files at once to tag a whole folder in one go.
What is DPI Converter?
Change the DPI tag an image carries, and see exactly how large it will print before you download it. DPI is metadata: a 3000 by 2400 image is 3000 by 2400 pixels whether it is labelled 72 or 300, and the tag only tells a printer or a layout app how tightly to pack those pixels. This tool patches the handful of bytes that store it, the pHYs chunk in a PNG or the JFIF density fields in a JPEG, so every pixel byte survives untouched. A second mode rescales the pixels instead, for when the print size has to stay fixed. Works with PNG and JPEG.
How do I use DPI Converter?
- Drop a PNG or JPEG onto the upload zone.
- Read the current tag; files with no tag are flagged, since software then falls back to its own default.
- Pick a target DPI from the presets or type your own.
- Choose whether to change the tag only, which is lossless, or to resample the pixels so the print size stays the same.
- Check the print size table, then download.
When should I use DPI Converter?
Use this when a print shop or a layout tool insists on a DPI value and the pixel count is already sufficient. To change the pixel dimensions themselves, use Image Resizer. To shrink the file without changing dimensions, use Image Compressor. To work out how many pixels a given print size needs, read the Inches column here.
Frequently asked questions
What is DPI and why does it matter?
DPI, dots per inch, is a metadata field telling printers and layout software how large to physically render an image. Screens ignore it entirely; printing uses it to decide how many pixels map to each inch of paper.
Does raising the DPI make my image sharper?
No, and this is the most common misunderstanding about DPI. Changing the tag adds no detail, because no pixels are added. A 600 by 400 image holds exactly 240,000 pixels whether it is tagged 72 or 300 DPI. Raising the tag makes it print smaller and denser, not sharper.
What is the difference between the two methods?
Changing the tag keeps every pixel and only rewrites the density field, so the file stays lossless and the image prints at a different physical size. Resampling keeps the physical print size and rescales the pixel count to match, which re-encodes the image; raising DPI this way still cannot recover detail that was never captured.
Will the file size or the pixel dimensions change?
In tag mode the pixel dimensions never change and the file grows by at most a few bytes, since a PNG without an existing pHYs chunk needs a new 21 byte one inserted. In resample mode both the dimensions and the file size change by design.
What DPI should I use?
300 is the standard for print, 150 for drafts and large format work viewed from a distance, 600 for fine art and line work, and 72 or 96 for screen only assets. If a tool demands a specific value and your pixel count is already adequate, tag mode satisfies it without touching the image.
Why is my JPEG DPI still wrong in some software?
A JPEG can carry a resolution in both a JFIF segment and an Exif block, and a few applications prefer Exif. This tool writes the JFIF value, which browsers, printers and the major layout apps read, and tells you when an Exif block is also present.
Why can I not set the DPI of a GIF, WEBP or SVG?
Those formats have no field for it. Only PNG and JPEG store a physical density tag. Convert to PNG or JPEG first if you need one.
Is my file uploaded anywhere?
No. Everything runs in your browser. Your files never leave your device, and there is no server component for this tool.
Tools that pair well with DPI Converter
- Image Resizer resize to exact pixels or %, free and in your browser.
- Image Compressor shrink file size, keep quality, free and in your browser.
- Image Converter png ↔ jpg ↔ webp, free and in your browser.
- Image Upscaler ai 2× and 4× upscaling, free and in your browser.