Find the Right Image Quality
Set how close to the original your images must stay, and Pixellin finds the quality that meets it. Every file shows the chosen quality and similarity score.
- On-device
- No sign-up
- Batch
- Free, no watermark
Drop images on the plate
or paste with Ctrl/⌘ V
Processed on this device
How it works
- 01Drop, choose or paste the images you want to tune.
- 02Choose a target: Balanced, High or Visually identical.
- 03Select Process and read each file’s chosen quality and similarity score.
- 04Download each file or select Download all for a ZIP.
Why use this tool
Three similarity targets
Choose Balanced for smaller files, High for a middle ground, or Visually identical for the strictest match.
See the numbers
Each result lists the quality setting chosen and its similarity score, so you learn what your images actually need.
Data for your workflow
Use the reported quality values to set defaults in your own build tools or export presets.
Supported formats
Use cases
Setting export defaults
Run a representative sample of your photos through and use the chosen quality values to set defaults in your editor or build pipeline.
Lighter thumbnails
For thumbnails and previews where tiny differences won’t be noticed, the Balanced target produces smaller files than the strictest setting.
Quality-critical work
Photographers and designers who can’t accept visible change can use Visually identical and check each score to confirm it.
Technical details
This is the optimizer with its target exposed. Like the other optimize pages, it encodes each image at several quality levels and compares each candidate with the original using SSIM, a structural similarity score where higher means closer to the original. The difference is that you choose the threshold: Balanced accepts a slightly lower score for smaller files, High sits in between, and Visually identical is the strictest.
Each file reports the quality value chosen and the similarity score achieved, which is useful when you want to understand an image set rather than just shrink it. If you’d rather not decide at all, the Image Optimizer applies the visually identical target automatically. If you need exact manual control over the quality number, the compress pages offer a slider instead.
Your files stay with you
This tool runs entirely inside your browser using Web Workers and WebAssembly. Your images are never uploaded, never stored on a server and never used to train AI. Close the tab and they’re gone. Learn more
Frequently asked questions
What is SSIM?
SSIM, the structural similarity index, compares two images based on luminance, contrast and structure, which tracks how people notice differences better than raw pixel math. A higher score means the compressed image is closer to the original. Pixellin uses it to judge each candidate quality level.
Which similarity target should I choose?
Use Visually identical for photography, product images and anything people will inspect closely. Use High for general website images. Balanced suits thumbnails, previews and backgrounds, where a slightly lower score is an acceptable price for a smaller file.
What is the best JPG quality setting?
There isn’t one number that suits every photo. That’s why this tool tests several levels and reports the one each image actually needed. Run a sample of your photos through and you’ll see the range that fits your kind of images.
How is this different from the Image Optimizer?
The Image Optimizer always uses the visually identical target and asks you nothing. This tool lets you choose between Balanced, High and Visually identical, and shows the chosen quality and similarity score for every file, so you can see and control the trade-off.
Related tools
Image Optimizer
Drop your images and let Pixellin choose the settings.
OPTIMIZE · JPGOptimize JPG
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OPTIMIZE · WEBPOptimize WEBP
Let Pixellin find the right WebP quality for each image.
OPTIMIZEOptimize AVIF
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CONVERTConvert to WebP
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