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Convert Image to 300 DPI

Write 300 DPI into a PNG or JPEG for KDP — and find out first whether the image has the pixels to print at your trim size, or only a new label. Runs in your browser; nothing is uploaded.

Your image never leaves this device. The check and the stamp happen here in your browser — no upload, no account, and no copy on our servers.

What a 300 DPI converter can and cannot do

Every "convert to 300 DPI" tool does the same thing: it rewrites a two-byte field in the file header. That is a legitimate, useful operation — InDesign, Affinity and KDP's previewer read it to size the image — and it takes a millisecond, which is why this one never uploads anything. What it cannot do is add pixels. An image that is 200 DPI at 6×9 inches is still 200 DPI at 6×9 inches after the label says 300.

So this tool diagnoses before it stamps. Pick the size you will print at and it tells you the real resolution the image reaches there, the largest size it holds 300 DPI at, and whether you need a bigger original, a smaller placement, or a genuine upscale.

The numbers behind the verdict

Effective resolution is pixels divided by printed inches, per axis, taking the softer axis — the same formula the Book Studioeditor uses for its DPI readout and its export preflight, so the verdict here is the verdict you would get there. 300 DPI is KDP's recommendation; under 200 is where KDP flags an image as low resolution.

Frequently asked questions

Does changing the DPI make my image higher resolution?

No. DPI is a number stored in the file's header that tells layout software how large to print the pixels. Rewriting it from 72 to 300 changes the label and nothing else — the same pixels now claim to be a smaller print. This tool tells you which situation you are in: enough pixels for your trim size, or a label on an image that will print soft.

What does KDP actually check?

KDP reads the resolution your images will print at from the pixel count and the size they are placed at, and flags anything under 200 DPI as low resolution; 300 DPI is the recommendation. A 1200×1800 pixel image is 300 DPI at 4×6 inches and 200 DPI at 6×9 inches, whatever the header says.

Why is my downloaded file named "label-only"?

Because the image does not have enough pixels for 300 DPI at the size you chose. We still write 300 into the header if you want it, but the name says what happened so a label-only file is never mistaken for a real 300-DPI one.

Are the pixels or the compression changed?

For PNG and JPEG, no — only the resolution field is rewritten, so the file is otherwise byte-for-byte what you gave us. WebP, GIF and BMP carry no printable resolution field, so those are re-saved as a PNG at the same pixel size with the label set.

Is my image uploaded?

No. Everything runs in your browser. There is no account, no server-side processing, and no copy of your image anywhere but your own device.

Go deeper

  • DPI

    How many dots of ink per inch an image contains at its printed size. KDP expects 300 DPI for print interiors and covers; screen images at 72 DPI print visibly soft.

  • Trim size

    The finished width and height of a printed book after the pages are cut. KDP publishes a catalog of standard trim sizes, and the one you pick affects both layout and printing cost.

SmartKDP is not affiliated with, endorsed by, or sponsored by Amazon. Amazon, Kindle, and Kindle Direct Publishing are trademarks of Amazon.com, Inc. or its affiliates.