DPI Converter
Inspect a JPG & PNG, set 300 DPI or custom resolution metadata without touching pixels, or calculate dimensions in inches, cm & mm. No upload—every calculation stays on your device.
Choose a JPG or PNG
Inspect its current DPI, calculate print size, or write a new resolution locally. Maximum file size: 25 MB.
Select imageHow to Prepare an Image for Print
Inspect resolution, update DPI headers, or resize for physical print dimensions in three steps.
Inspect the Source
Choose a JPG or PNG and review its pixel dimensions, current resolution metadata, and calculated physical print size.
Choose the Operation
Update DPI metadata only (preserving pixels byte-for-byte), or enter a physical print size in inches, cm, or mm.
Verify & Download
Check output pixels, effective DPI, and print quality guidance, then download your updated JPG or PNG file.
Why Use Pinatool’s DPI Converter?
Lossless DPI Header Update
Change 72 DPI to 300 DPI or 600 DPI in seconds without re-encoding or altering a single pixel of your image.
Real Print Size Calculator
See exact physical dimensions in inches, centimeters, and millimeters along with honest effective-DPI quality checks.
Browser-Local Processing
Your files are processed directly in your browser and are not uploaded to Pinatool's servers.
Frequently Asked Questions
Common questions about DPI vs. PPI, 300 DPI print requirements, and physical print sizes.
Does changing DPI improve image quality?
No. DPI metadata describes how densely existing pixels should be placed on paper. It does not add detail. Use the print-size mode when you intentionally need different pixel dimensions, and check the original effective DPI before enlarging.
Can I change a JPG or PNG to 300 DPI without resizing it?
Yes. Choose "Change DPI only" and enter 300. Pinatool updates the standard resolution metadata in your JPG or PNG file while leaving its pixel dimensions completely unchanged.
What is a good DPI for printing?
For raster images, PPI is the more precise term for pixels per printed inch, although DPI is commonly used by upload forms and print software. Many close-viewed photo prints target about 300 pixels per inch, while larger posters viewed from farther away may work well at 150–200 DPI. Your printer, paper, and viewing distance determine the real requirement.
Why does another app show a different print size?
Apps do not all interpret missing or conflicting resolution metadata the same way. Some assume 72 or 96 DPI. Pinatool reports where recognized metadata came from and writes standard resolution fields, though a print dialog can still override them.
Are my images uploaded to any server?
No. Reading resolution, calculating print size, updating metadata, resizing, and downloading all happen 100% locally in your browser.
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