KBSnap
English

Resize image to 640×480

4:3 · 0.31 MP · prints at 5.4×4.1 cm at 300 dpi

  • No upload
  • Exact target size
  • Batch ready

Drag images here, or click to choose

JPG / PNG / WebP / HEIC · up to 25MB each · batch supported

Files never leave your device — everything runs in your browser.

Width
px
Height
px
Fit mode
Output format
Allow upscaling
Quality
88%

What 640×480 is used for

  • Legacy attachment limits in email systems
  • Embedded images in old documents
  • Low-bandwidth web forms
  • Machine-learning dataset normalisation

4:3, 0.31 MP. Small enough that a batch of 200 stays under 10 MB total.

Pixels are not DPI

A file with 640×480 pixels carries no physical size until someone prints it. At 300 dpi that is 5.4×4.1 cm; at 150 dpi it is twice as large and half as sharp. Forms that ask for “300 dpi” and “640×480 px” are asking for the same thing in two languages — this tool satisfies both, and stamps the requested dpi into the file.

Why it will not upscale by default

Padding a 400×300 image to 1920×1080 does not add detail: it invents pixels by interpolation, and the result looks soft at every zoom level. The upscale switch exists for the cases where you truly must (a platform that rejects anything smaller), but the honest answer is to start from a bigger source.

Cropping, not stretching

Changing the aspect ratio is a destructive decision. “Cover” fills the frame and cuts the overflow; “contain” keeps everything and adds padding; “stretch” distorts on purpose. Default is cover with a centre anchor, which is right for photos and wrong for documents — pick per batch.

Frequently asked questions

Do I lose quality going to 640×480?
Downscaling with high-quality smoothing loses very little, and often looks cleaner than the original because camera noise averages out. Upscaling always softens. Either way the output is re-encoded once, so avoid repeating the process.
Can I keep the original aspect ratio?
Yes — that is the default behaviour with “cover”. Type only one dimension and the other follows. Turn on “allow upscale” only if the source is smaller than 640×480.
Does resizing also compress?
Yes. Re-encoding to JPG or WebP reduces the file size as a side effect, usually far more than the dimension change alone. If you need an exact byte target, use the compression tool instead — it searches for it.
Is this safe for confidential images?
The image is decoded and re-encoded inside your tab. No request carries the file anywhere; the only network activity on this page is loading the page itself.

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