Image Processor
Upload an image and apply basic transformations like resize, greyscale, or rotate. Note: Jimp operations are client-side. Larger images may take time.
Drag 'n' drop an image here, or click to select
What This Tool Does
Basic image edits — resizing a photo down for the web, converting to greyscale, straightening a rotated scan, nudging brightness or contrast — don't need a full photo editor. Upload an image, apply one of these adjustments, and download the result, entirely without the file ever leaving your browser.
How to Use It
Drag an image into the upload area (or click to select one), then choose an Operation: Resize, Greyscale, Rotate, Brightness, or Contrast. Resize asks for a width and/or height in pixels — leave either at 0 and it scales automatically to preserve the original proportions. Rotate asks for an angle in degrees, and Brightness/Contrast each take a value from -100 to 100. Click Apply and the processed version appears next to your original, with its own download link.
The Formula
This tool runs on a real build of Jimp, a JavaScript image-processing library, loaded directly in your browser rather than sent to a server. Only five operations are exposed on this page — resize, greyscale, rotate, brightness, and contrast — each calling straight through to Jimp's own equivalent method. Brightness and Contrast are passed to Jimp as a fraction from -1 to 1, so this tool's -100-to-100 input is simply divided by 100 first. One detail worth knowing: whatever format you upload — PNG, JPEG, BMP, or TIFF — the processed image downloads in that exact same format; there's no option to convert between formats as part of processing.
A Worked Example
Upload a 1200×900 photo and choose Resize with Width set to 300 and Height left at 0: since 0 means "auto," Jimp scales the height proportionally to match, landing on 300×225 — the same 4:3 ratio as the original, just smaller. Switch to Rotate on that same image with an angle of 90, and the output comes back as a 225×300 image with the content turned a quarter-turn — width and height swap because a 90-degree rotation turns a landscape image into a portrait one.
FAQ
- Are my images uploaded to a server?
- No, all image processing happens entirely in your browser using Jimp. Your images never leave your device.
- What image formats are supported?
- PNG, JPEG, BMP, GIF, and TIFF files are supported for both input and output — output is always the same format as the file you uploaded, since this tool does not convert between formats.
- What edits can I apply?
- Resize, rotate, adjust brightness and contrast, and apply a greyscale filter.