Image converter and compressor
Name thefile size.Kiln hits it.
Convert between PNG, JPG and WebP, squeeze a photo to exactly 200 KB, knock out a solid background, and pack several images into one PDF. Everything runs in this tab. Nothing is uploaded.
Free. No account. Batches welcome.
How it works
Drop, set, save.
- 01
Drop your images
Drag in a handful, paste from the clipboard, or choose files. Kiln opens whatever your browser can decode.
- 02
Pick a format and a size
Choose PNG, JPG or WebP, then set a quality or type the file size you need. Resize, crop or remove a solid background if needed.
- 03
Save one, a ZIP, or a PDF
Compare against the original, then download a single file, the whole batch as a ZIP, or pack several images into one PDF.
What Kiln does
The everyday jobs, plus a few extras.
Plain tools for converting and shrinking images, with some things that usually need three different websites.
- Target size
Type 200 KB. Get 200 KB.
Kiln searches for the highest JPG or WebP quality that fits under your limit. If no quality gets there, it shrinks the dimensions in small steps until it does.
- Compress
Presets for web, email and print
One tap sets format, quality and longest side for common jobs — then fine-tune with the slider or a KB target.
- Background
Knock out solid backgrounds
Flood-fill from the edges to remove white or coloured studio backdrops, with tolerance and soft edges. Undo anytime. Best for product shots, not complex photos.
- PDF
Mix images into one PDF
Put two, three or a whole queue into a single PDF — one image per page, fitted to A4 or Letter, built in your browser.
- Curve
See the quality curve first
For each image, Kiln measures file size and fidelity from quality 10 to 95 and marks a sweet spot, so you stop guessing at the slider.
- Compare
Drag to compare
A slider cuts across the picture between the original and the result, using the same pixels at the same scale.
- Batch
One set of choices, many files
Apply the same format, size and naming to a whole queue, then download everything as a ZIP or one PDF.
- Shape
Resize, crop, rotate, flip
Cap the longest side, or crop to 1:1, 4:5, 16:9, 3:2 and the 1.91:1 link-preview ratio. Fix sideways photos in one click.
- Icons
Favicon pack from any image
One picture becomes favicon.ico, an Apple touch icon, Android icons and a web manifest, zipped and ready for your site.
- Palette
Pull colours out of a picture
Get five dominant colours and copy their hex codes.
- Finish
Watermark and file names
Stamp text in a corner, and name outputs with patterns like {name}-{w}x{h}.
- Private
Nothing leaves your device
Your browser decodes and re-encodes every image. There is no upload, no account and no tracking.
The curve
Read the curve, then stop where it stops paying.
Past a point, higher quality adds bytes and little else. Kiln draws that curve for your own image.
Questions
Short answers.
Are my images uploaded anywhere?
No. Kiln decodes and re-encodes images with your browser's own image tools. The files stay in your device's memory until you close or reload the tab.
Which formats can I open and save?
You can open anything your browser can decode, usually PNG, JPG, WebP, GIF, BMP, SVG, AVIF and ICO. You can save as PNG, JPG or WebP. Animated GIFs are read as a single frame.
Why doesn't quality change my PNG?
PNG is lossless, so there is no quality dial. To make a PNG smaller, resize it, use Target size (which shrinks the dimensions), or switch to WebP.
Does Kiln remove location data from photos?
Re-encoding drops EXIF metadata such as camera model and GPS position in practice. If it matters, check the saved file yourself before sharing it.
My Target size result has fewer pixels. Why?
When even the lowest usable quality is still over your limit, Kiln reduces the dimensions step by step until the file fits. The stats under the preview show the final size.
Is there a size limit?
Kiln sets none. Very large images can run into your device's memory or your browser's canvas limits, and those files may fail to open.
How does background removal work?
Kiln samples the edge colours and flood-fills matching pixels so studio-style solid backgrounds become transparent. It is not an AI cutout — busy scenes or soft gradients may leave crumbs. Use Undo if the result looks wrong, then raise or lower tolerance.
Can I put several images in one PDF?
Yes. In the converter, use Export PDF. Each image becomes its own page, fitted to A4 or Letter with margins. You can include the whole queue or only the selected image.
Drop a photo. Pick a size.
The converter opens with a sample picture so you can try every control before using your own files.