Last tested
What does this image resizer do?
Vaultaire changes the pixel dimensions of one still JPEG, PNG, or WebP. It keeps the full composition and aspect ratio, applies stored display orientation, and makes a new web-ready image.
The selected file is processed in a dedicated browser worker. Pica's pinned JavaScript resampler handles photos and graphics. Pixel art uses nearest-neighbor sampling. No resize API receives the file.
How do I resize an image to exact pixel dimensions?
- Choose an image. Select one still JPEG, PNG, or WebP. The browser checks the file before decoding it.
- Set one dimension. Use the longest edge, width, height, percentage, or a maximum box. The other side is calculated for you.
- Download the checked copy. The new file stays locked until its dimensions, decoded pixels, and supported metadata pass.
Can an image be resized without losing quality?
Not literally. A smaller raster contains fewer pixels. A larger raster contains more samples, but no new captured detail. JPEG and lossy WebP can also change pixel values during encoding.
This tool makes the tradeoff inspectable. Photo mode uses a fixed high-quality resampling filter. The receipt reports the requested dimensions, the decoded output dimensions, format, encoder setting, file size, orientation handling, transparency, and supported metadata result.
Pica documents its browser resampling limits in the project repository. The browser APIs used for local decode and output are defined by createImageBitmap and OffscreenCanvas.convertToBlob.
How do I resize an image to a KB or MB size?
Two different jobs share the word "resize", and the tool you need depends on which one you mean.
Pixels are dimensions. KB are file size. This page changes dimensions: it sets the width and height in pixels, and the file size changes as a side effect that you cannot dial in. Use it when a form asks for 600 by 600 pixels, or when an image is too large for a layout.
To hit a file-size limit such as 20 KB, 50 KB, 100 KB, or 200 KB, use the image compressor. It takes the number in KB or MB as a ceiling, tests encoder qualities, and reports the real output bytes. It never changes dimensions to force a fit.
Aggressive limits need both tools in order. A full-resolution phone photo holds more detail than 20 KB or 50 KB of JPEG can carry at any quality. Reduce the width here first, then set the ceiling in the compressor.
JPEG, PNG, or WebP output
| Format | Best for | Transparency | Setting |
|---|---|---|---|
| JPEG | Photos and broad compatibility | No. A background choice is required. | Encoder quality |
| PNG | Graphics, text, and exact alpha | Yes | Lossless output encoding |
| WebP | Smaller modern web images | Yes, when the browser encoder supports it | Encoder quality |
The browser tests each encoder after you choose a file. A format is disabled if the returned file type, signature, or test decode does not match the request.
Private image resizing without an upload
Cloudflare serves this page and its static code. After selection, the file moves only between the page and a same-origin worker in your browser. Client analytics send fixed action events to Vaultaire's PostHog proxy, the only connection the page's Content Security Policy allows, and the image is never part of them. A later page navigation still makes a normal web request.
Resizing creates a new raster and does not preserve the original encoded image data. Supported source metadata is reported, not copied, and scanned again in the output. This does not detect or remove every invisible pixel watermark or proprietary steganographic signal.
Image resizer FAQ
How do I resize an image to exact pixel dimensions?
Choose an image, select Width or Height, and enter the target in pixels. Vaultaire calculates the other side and keeps the aspect ratio locked.
How do I resize an image to a KB size such as 50 KB or 100 KB?
Use the image compressor for that. Pixels are dimensions and KB are file size, so they are two different jobs. This resizer sets width and height in pixels, and the file size changes only as a side effect. The compressor takes a KB or MB figure as a ceiling, tests encoder qualities, and reports the real output bytes. For a tight limit such as 20 KB or 50 KB, reduce the width here first, then set the ceiling in the compressor.
Does the image resizer upload my photo?
No. The selected image is read, resized, encoded, and verified inside your browser, with no upload or processing API. PostHog receives fixed action and completion events, never image bytes, filenames, dimensions, or settings. The route's Content Security Policy allows only Vaultaire's PostHog proxy for those events.
Can I resize an image without losing quality?
Every resize changes the pixel grid. Downscaling removes pixels, enlargement does not add captured detail, and JPEG or WebP encoding can add compression loss. The tool uses a controlled resampling method and verifies the output rather than claiming zero quality loss.
Does changing pixel dimensions change DPI or PPI?
Pixel dimensions and print density are separate. This tool changes the pixel grid. It does not set a requested DPI or PPI value.
Does resizing remove photo metadata?
The new file does not copy supported source EXIF, XMP, location, origin, or C2PA records. Vaultaire scans the output again and blocks download if supported private or origin metadata remains. It cannot rule out every proprietary or pixel-embedded signal.