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修改图片 DPI

修改图片的 DPI

在浏览器中运行 · 无需上传

此工具及本页说明目前仍为英文。功能完全相同：一切都在你的浏览器中运行。

Drag & drop images here

or

JPG, PNG, WebP, AVIF, GIF, BMP, TIFF, SVG, HEIC or PSD/PSB · one or many

Your files stay on your device. Nothing is uploaded.

  • 任何内容都不会离开你的设备
  • 服务器不限制文件大小
  • 无需注册，无水印
  • 免费

How to change the DPI of an image

  1. Choose your JPG or PNG images.
  2. Pick 300 DPI, another common value, or type your own.
  3. Press Set DPI and download. Each result shows the size it will print at.

What DPI really means

DPI only tells printers and layout apps how big to print the image. A 3000 × 2000 pixel photo prints 25.4 × 16.9 cm at 300 DPI, or 105.8 × 70.6 cm at 72 DPI. The pixels, and so the sharpness, stay exactly the same.

If a print shop asks for "300 DPI", check that the print size shown is at least as large as your print. If it is smaller, the image needs more pixels, and changing the DPI won't add detail.

What this tool changes

  • JPG: the DPI in the JFIF header, the EXIF resolution and Photoshop's resolution info, so Windows, macOS, Photoshop, Word and InDesign all see the same value.
  • PNG: the pHYs chunk that stores the physical pixel size.
  • Nothing else: the image data is copied byte for byte, with no re-compression.

Your images stay on your device

Everything happens in your browser. Your images are never uploaded, so private photos and client work stay with you.

常见问题

Does changing DPI make my photo sharper?

No. DPI is only a label for the print size. To print larger at the same sharpness you need an image with more pixels.

Why only JPG and PNG?

They are the formats where printers and layout apps reliably read a DPI value. Convert other images to JPG or PNG first with the Image Converter.

Is the quality reduced?

No. Only the DPI fields are rewritten; the pixels are not touched or re-compressed.

Are my images uploaded?

No. They are processed in your browser and never sent anywhere.