Check image DPI and convert to any resolution.
Find out the DPI of any image, see print sizes at different resolutions, and convert to 300 DPI for professional printing. Free, private, instant.
Drop an image here, or click to browse
JPG, PNG, or WebP - DPI metadata is read from JFIF headers
How to check image DPI.
Upload your image
Drag a JPG, PNG, or WebP file onto the upload area. DPI metadata is read from the file header instantly.
Review DPI and print sizes
See the detected DPI, pixel dimensions, and calculated print size. The quality assessment shows print dimensions at 72, 150, and 300 DPI for comparison.
Change DPI if needed
Switch to the Change DPI tab, pick your target resolution, and download the resampled image. Common targets: 300 for print, 72 for web, 150 for large format.
DPI guide for common print sizes.
The pixel dimensions you need depend on both your target print size and the DPI requirement. Here are the minimum pixel counts for common print products at their recommended DPI.
300 DPI (standard photo quality)
4x6 inch print: 1200x1800 pixels. 5x7 inch: 1500x2100. 8x10 inch: 2400x3000. A 12 MP phone camera (4000x3000) prints sharply up to 10x13 inches. Most photo labs require 300 DPI files. If your image is below this threshold, the printed output will appear soft or pixelated.
150 DPI (large format / posters)
24x36 inch poster: 3600x5400 pixels. 20x30 inch canvas: 3000x4500. Large prints are viewed from several feet away, so the lower pixel density is not visible. A 24 MP camera file (6000x4000) covers a 40x26 inch poster at 150 DPI comfortably.
72 DPI (screen only)
Website images, email headers, social media posts. The DPI value is ignored on screens - what matters is the pixel count. A 1200x630 OG image at 72 DPI looks identical to one at 300 DPI on any display. Save at 72 DPI for smaller file sizes when the image is web-only.
Frequently asked questions.
What is DPI and why does it matter?
DPI (dots per inch) tells printers how many pixels to pack into each inch of paper. A 3000x2000 image at 300 DPI prints at 10x6.67 inches. The same image at 72 DPI prints at 41.7x27.8 inches but looks blurry because the pixels are spread too thin. DPI only matters for print - on screens, the pixel dimensions are what count. Most phones and cameras embed 72 DPI by default, which is fine for web but needs changing for professional print work.
How does the DPI checker read my image DPI?
The tool reads the JFIF header in JPEG files, which stores horizontal and vertical density values along with a unit flag (pixels per inch or pixels per centimeter). If the header says unit=1 (inches), the density values are the DPI directly. If unit=2 (centimeters), they are multiplied by 2.54 to convert. PNG and WebP files typically do not store DPI metadata, so the tool defaults to 72 DPI for those formats.
What DPI do I need for printing?
Standard photo prints (4x6, 5x7, 8x10): 300 DPI gives excellent quality. Large format posters (24x36 inches): 150 DPI is sufficient because viewers stand further back. Billboards: 30-72 DPI works because viewing distance is measured in feet. Documents and text: 300 DPI minimum for sharp text. Business cards: 300 DPI at the final print size. The print quality assessment section shows your image size at common DPI values so you can judge what works.
What does the DPI converter do?
The converter resamples your image to match the target DPI at the current physical dimensions. If your image is 3000x2000 at 72 DPI (41.7x27.8 inches) and you convert to 300 DPI, the tool resizes the image to 12500x8333 pixels to maintain the same physical print size at the higher resolution. This upscaling adds pixels but does not add detail - it is useful for meeting print submission requirements, not for improving image sharpness.
Does changing DPI change image quality?
Changing DPI metadata alone (without resampling) does not affect image quality at all - it only changes how a printer interprets the pixel dimensions. When the converter resamples to a higher DPI, it adds interpolated pixels which can introduce softness. Resampling to a lower DPI removes pixels, reducing file size and detail. For best results, capture images at the resolution you need rather than upscaling later.
Why does my image say 72 DPI?
Most digital cameras, phones, and screenshot tools default to 72 DPI because that was the original Macintosh screen resolution and became the web standard. The actual pixel count determines image quality - a 4000x3000 photo at 72 DPI contains the same data as the same photo at 300 DPI. The DPI tag just tells printers how to scale it. Many photo editors strip or ignore DPI metadata entirely.
Are my images uploaded to a server?
No. DPI metadata is read from the file header bytes directly in your browser using a DataView on the first 20 bytes of the JFIF segment. The DPI conversion resamples using the Canvas API locally. Your image never leaves your device. Verify by opening browser developer tools (F12) and checking the Network tab while using the tool.