Pixel dimensions
Width × height describes how many samples the image contains. Fewer pixels usually means fewer bytes and less detail; enlarging dimensions cannot recover detail that was never captured.
Compress & Resize
Hit a specific KB target, resize by dimensions, and use prefilled size pages for forms, social images, thumbnails, or web assets.
Quick decision guide
Make an image meet upload requirements in the right order
Upload limits often combine format, width and height, aspect ratio, file size, and sometimes DPI. Treat them as separate checks. First match the required shape and pixel dimensions, then reduce bytes, and finally verify the downloaded file instead of assuming one setting solved every requirement.
| What you need | Start with | Why |
|---|---|---|
| The form gives a maximum or exact KB value | Compress Image to KB | Enter the target directly, or use a preset such as 20KB, 50KB, 100KB, or 1MB. |
| The requirement gives width × height in pixels | Resize by Dimensions | Set exact pixel dimensions and decide whether to preserve, crop, or change the source shape. |
| You only need a proportional smaller copy | Resize by Percentage | Scale both dimensions together without calculating the new width and height yourself. |
| A portal rejects files below a minimum KB | Increase Image Size KB | Increase encoded bytes for a minimum-size rule; this does not create new visual detail. |
| A print workflow asks for a DPI value | Set Image DPI | Change resolution metadata only after confirming that the pixel dimensions are already sufficient. |
| You need to inspect before or after editing | Image Size Checker | Verify format, pixel dimensions, aspect ratio, and file size on the actual file. |
| The destination has a known social or web layout | Resize Image for Website | Start from a website or platform preset, then check cropping and final bytes. |
All 22 Compress & Resize tools
Select a tool to open it. All listed tools are live.
C
Compress Image to KB
/tools/compress-to-kb/
R
Resize by Dimensions
/tools/resize-by-dimensions/
R
Resize by Percentage
/tools/resize-by-percentage/
I
Increase Image Size KB
/tools/increase-image-kb/
S
Set Image DPI
/tools/set-image-dpi/
I
Image Size Checker
/tools/image-size-checker/
C
Compress Image to 20KB
/tools/compress-image-to-20kb/
C
Compress Image to 30KB
/tools/compress-image-to-30kb/
C
Compress Image to 50KB
/tools/compress-image-to-50kb/
C
Compress Image to 100KB
/tools/compress-image-to-100kb/
C
Compress Image to 200KB
/tools/compress-image-to-200kb/
C
Compress Image to 300KB
/tools/compress-image-to-300kb/
C
Compress Image to 500KB
/tools/compress-image-to-500kb/
C
Compress Image to 1MB
/tools/compress-image-to-1mb/
R
Resize Image to 1080x1080
/tools/resize-image-to-1080x1080/
R
Resize Image to 1920x1080
/tools/resize-image-to-1920x1080/
R
Resize Image to 1280x720
/tools/resize-image-to-1280x720/
R
Resize Image to 512x512
/tools/resize-image-to-512x512/
R
Resize Image for Instagram
/tools/resize-image-for-instagram/
R
Resize Image for YouTube Thumbnail
/tools/resize-image-for-youtube-thumbnail/
R
Resize Image for LinkedIn
/tools/resize-image-for-linkedin/
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Resize Image for Website
/tools/resize-image-for-website/
How the key settings affect the result
These terms describe different parts of the job. Knowing which one the destination checks prevents unnecessary quality loss.
Aspect ratio
Width divided by height describes the image shape, such as square or widescreen. Changing ratio requires cropping, padding, or stretching; only cropping and padding preserve natural proportions.
File size
KB and MB measure encoded bytes, not visual dimensions. Format, pixel count, image detail, metadata, and encoder settings all affect the final number.
Quality
For lossy outputs, quality controls how aggressively detail is simplified. Lower quality often reduces bytes, but fine text, hair, foliage, and sharp edges reveal damage first.
DPI
DPI is mainly print-resolution metadata. Changing 72 to 300 DPI without adding pixels does not make the image sharper; print size, DPI, and pixel dimensions must agree.
Format
A photo often reaches a low byte target more easily as JPG or WebP than PNG. Graphics with transparency or hard edges may need PNG despite the larger file.
What you can do in the browser
The resize and compression work happens locally in the browser: your selected image is decoded, processed, and downloaded on the same device. Very large images can still hit browser memory limits, especially on phones, because decoded pixels use much more memory than the compressed file on disk.
- Read file size, pixel dimensions, format, and aspect ratio before changing anything.
- Resize to exact pixels or scale both dimensions by a percentage.
- Compress toward a target KB value and compare the resulting image.
- Set DPI metadata or increase encoded bytes for a portal with unusual minimum rules.
- Create destination-specific copies while preserving the untouched original.
Common failure cases
Check these before downloading or submitting the result.
Compressing before resizing
A full-resolution camera photo wastes the byte budget on pixels the destination will discard. Match dimensions first, then compress.
Confusing pixels with KB
A 1080×1080 image is not guaranteed to be under 100KB. Dimensions and encoded file size require separate checks.
Forcing the wrong aspect ratio
Typing an exact width and height can stretch faces or logos. Crop or pad when the source and destination shapes differ.
Using PNG for a tiny photo target
Lossless PNG can remain large even at low dimensions. If transparency is unnecessary and the form permits it, a photo format is often easier to fit.
Upscaling to improve quality
More output pixels do not add genuine source detail. Upscale only to satisfy dimensions and inspect softness before submission.
Trusting the preview instead of the download
Portals evaluate the exported file. Run the downloaded result through Image Size Checker and confirm every stated limit.
Complete workflows
Use the tools as a sequence when the destination has more than one requirement.
Government or job application form
- Write down accepted format, required dimensions, ratio, and minimum or maximum KB.
- Use Resize by Dimensions first; crop or pad instead of stretching.
- Compress to the KB limit, download, and verify the final file with Image Size Checker.
Social image or thumbnail
- Start from the relevant preset or exact destination dimensions.
- Inspect the crop so faces and text remain inside the visible area.
- Compress the exported copy only as far as needed, then preview it at normal display size.
Website image
- Choose the largest pixel width the layout actually renders.
- Export in a format supported by the site and preserve transparency only when needed.
- Compress, compare visible detail, and keep a higher-quality source for future sizes.
Print handoff
- Confirm the intended print dimensions and required DPI with the recipient.
- Make sure the source has enough pixels for that combination.
- Set DPI metadata last and verify that the operation did not substitute for missing source resolution.