Optimize & Print
Change Image DPI
Set any DPI (72, 150, 300, 600…) on JPG and PNG images without recompressing a single pixel. Runs locally in your browser.
Metadata-only change, done locally — zero quality loss, nothing uploaded.
To change an image's DPI to 300 without losing quality, drop JPG or PNG files above, pick 300 — or 72, 150, 600, any custom value — and download. DPI is a print-density label, not resolution: only the density metadata is rewritten in your browser, pixels are never resampled, and nothing is uploaded.
Honest limits
- JPG and PNG only — DPI lives in format metadata (JFIF/EXIF and pHYs).
- Metadata-only change: pixels are never resampled, so sharpness in print still depends on pixel dimensions.
Need more than a browser can do? Desktop browsers go further than phones — and Media Moana converts at scale on hosted infrastructure.
How it works
Drop JPG or PNG files
Batch works — set a whole folder to 300 DPI at once.
Pick the DPI
Choose 72 / 150 / 300 / 600 or type any value.
Download
Only the density metadata changes — pixels and quality are untouched.
Frequently asked questions
Is this safe? Do my photos get uploaded?
No upload happens — ever. Changing DPI runs entirely inside your browser using WebAssembly. Your files never leave your device, nothing is stored on any server, and the tool even keeps working if you go offline after the page loads. That's also why there are no file size limits, no queues and no sign-up.
Does changing DPI change image quality or size?
No. DPI is just a metadata field — a note telling printers and layout software how many pixels to place per inch of paper. Your image keeps exactly the same pixels; this tool rewrites only the density metadata (JFIF/EXIF for JPG, pHYs for PNG), so there is zero recompression and zero quality change.
Can you increase the DPI of an image from 72 to 300?
Yes, instantly — because nothing about the picture itself needs to change. A photo labelled 72 DPI contains exactly the same pixels as the identical photo labelled 300 DPI; the number is only a print-density note read by layout software and print portals. This tool rewrites that note, so the file passes 300 DPI checks. Genuinely adding pixels for a bigger print is a different job — that needs an upscaler, and it is lossy.
Why do print services ask for 300 DPI?
300 pixels per inch is the standard threshold at which printed photos look sharp at normal viewing distance. Many print portals simply check the DPI metadata field and reject files below 300 — even when the image has plenty of pixels. Setting the field to 300 satisfies the check; whether the print actually looks sharp depends on the pixel dimensions (e.g. 3000×2400 px prints sharply at 10×8 inches).
What is 300 DPI in pixels?
There is no single number — it depends on the print size, because pixels = DPI × inches. At 300 DPI, a 4×6 inch print needs 1200×1800 pixels, 5×7 needs 1500×2100, 8×10 needs 2400×3000, and A4 needs about 2480×3508. If your image has at least that many pixels for your target size, setting the DPI field to 300 makes it both pass portal checks and print sharply.
How do I check my image's DPI?
Use the companion Image DPI Checker — drop files in and it reads the JFIF, EXIF or pHYs density metadata locally, showing each image's stored DPI, pixel dimensions and largest sharp print size. On Windows, right-click a file and open Properties → Details; on macOS, open the image in Preview and press Cmd+I. If no DPI is stored, most software assumes 72.
What DPI should I choose?
300 for photo printing and most submission portals, 150 for large-format posters viewed at a distance, 72 or 96 for screen-only use. If a portal told you a specific number, use exactly that.
Can I change the DPI of multiple images at once?
Yes — set a whole folder to 300 DPI in one pass. Each file gets only its density metadata rewritten, locally, so even big batches finish in seconds and download individually or as a single ZIP.
Is there a file size or quantity limit?
There is no hard limit. Server-based converters cap uploads because your files consume their bandwidth and CPU; here rewriting density metadata happens on your machine, so the only practical limit is your device's memory. Desktop browsers comfortably handle very large files and big batches.