About This Tool
Contrast Adjuster strengthens or softens the difference between light and dark areas. Higher values increase separation; lower values create a softer look.
How to Use
- Choose or drop an image and check its orientation, file size, and pixel dimensions.
- Set the contrast, choose the output format, and adjust quality or the background color where available.
- Click “Apply changes” to compare the original and result, including actual pixel dimensions and file size.
- Download when you are satisfied. “Reset settings” restores the default effect; “Clear” removes the files and results.
Settings explained
- Contrast ranges from 0% to 200% and defaults to 100%. At 0%, tonal differences are greatly reduced.
Supported Formats
- Input: JPG/JPEG, PNG, or static WebP. GIF, animated PNG, and animated WebP are not supported.
- Output: JPG, PNG, or WebP if supported by your browser. Most edits keep the input format by default; opacity and rounded-corner tools default to PNG.
Image Processing Notes
Changes apply to the full original image and keep its loaded pixel width and height by default. The preview may appear smaller; the downloaded file contains the full processed image.
- Increasing contrast can brighten highlights and deepen shadows, but may also remove detail in those areas.
- Lower contrast does not restore missing tonal detail. Check both highlights and shadows.
- PNG and WebP support transparency. JPG blends transparent areas with your chosen background color, which is white by default. The preview’s checkerboard is not included in the download.
- Downloads contain the full processed image. Saving again can change file size and compression details, and usually removes original EXIF, GPS, and similar information. Keep your original file.
Each image can be up to 100 MiB. Files over 50 MiB trigger a high-memory-use notice. Original and output images are limited to 16 megapixels, with each dimension no greater than 16,384 pixels. Some operations have lower limits; resize the image first if prompted.
Privacy
Images are processed entirely in your browser and are never uploaded to a server.
Files are not saved automatically. Download any results you want to keep before clearing or leaving the page, and keep your original file.
FAQ
What does 100% contrast mean?
It keeps the original contrast. Values below 100% soften light/dark differences; values above 100% strengthen them.
Does more contrast always mean more clarity?
No. A moderate increase can help a subject stand out, but too much may lose highlight and shadow detail.
Can lowering contrast recover overexposed detail?
It cannot restore unrecorded detail. It only changes the light and dark relationships of existing pixels.
Will the download keep the original dimensions?
The tool preserves the loaded image’s pixel dimensions. A smaller preview does not make the download smaller. Output format and quality can still affect file size and detail.