Convert Image Formats Without Uploading Your Files
Choose an output format, drop your images, and convert between JPG, PNG and WebP entirely in your browser.
- Processed locally
- No account required
- Batch up to 12 images
Drop images here
or
JPG, PNG or WebP · Up to 12 images
Images 0 / 12
Processed in your browser. Your images are not uploaded to SkyyCast.
Your result will appear here
Add an image on the left to get started.
When should I use WebP?
WebP is usually the best default for the web: at the same visual quality it's typically smaller than JPEG, and it supports transparency the way PNG does. Use it for website images, article photos and anything headed to a modern browser. The one reason to avoid it is a destination that specifically requires JPEG or PNG, such as some print workflows or older software.
When should I keep PNG?
Keep PNG for graphics, screenshots with text, logos, or anything with transparency that needs to stay perfectly lossless. PNG doesn't compress photographic detail efficiently, so a photo saved as PNG is usually far larger than the same photo as JPEG or WebP — convert it if file size matters and you don't need pixel-perfect lossless output.
When is JPG better?
JPG remains the safest choice for maximum compatibility — every browser, device, email client and piece of software opens it without question. Use it for photos without transparency when you specifically need that universal support, or when a destination (like some ad platforms or legacy systems) requires it.
Does converting JPG to PNG improve quality?
No. Converting a JPG to PNG changes the container and makes any further edits lossless from that point on, but it cannot restore detail JPEG's compression already discarded when the file was first saved. A JPG converted to PNG will usually end up larger, not better — the quality ceiling was set the moment the original was saved as a JPG.
Does WebP always produce a smaller file?
Usually, but not always. WebP tends to beat JPEG and PNG at the same visual quality, but a specific image's content, its existing compression and the quality setting you choose all affect the result. This tool shows you the actual before/after size for every image rather than assuming WebP will win.
What happens to transparency when converting to JPG?
JPEG has no way to store transparent pixels. Converting a transparent PNG or WebP to JPG fills every transparent area with a solid background color — this tool warns you before that happens and lets you pick the color (white by default), rather than silently producing an image with unexpected solid patches. If you need to keep transparency, convert to PNG or WebP instead.
Does converting change an image's dimensions?
No. This tool only changes the format and encoding — width and height stay exactly as they were. If you also need a different size, use the Image Resizer before or after converting.
Does SkyyCast upload my images?
No. Every image is read, measured and re-encoded by your own browser using the File API, <canvas> and, where supported, createImageBitmap. Nothing is sent to SkyyCast or any other service, no account is needed, and closing or reloading the page discards everything.
Frequently asked questions
Is WebP supported everywhere?
WebP decoding is supported in all current major browsers. This tool also checks that your specific browser can encode WebP before offering it, and disables the option with an explanation if it can't — so you're never shown a format your browser quietly can't produce.
Can I convert several images to the same format at once?
Yes. Add up to 12 images, pick one output format, and press Convert to process all of them. If one image fails, the rest still complete — the failed one is clearly marked with its own explanation.
Can I convert the same images to a different format afterward?
Yes. Pick a different output format and press Convert again — it reprocesses every image currently in the list against the new format.
What happens if I try to convert an image to the format it's already in?
That image is marked as nothing to convert rather than silently re-saving an identical copy, since there's no actual format change to make.
Does this also compress my images?
Converting to a lossy format (JPG or WebP) does re-encode the image at the quality level you choose, which can reduce file size. If your main goal is hitting a specific file size rather than changing format, use the target-size compressor instead.
More free tools
See all free SkyyCast tools. Need smaller files instead of a different format? The target-size compressor gets an image under 100 KB, 200 KB or any size you choose. Need exact dimensions? The Image Resizer resizes by width/height or percentage. Turning images into a document instead of another image format? The Image to PDF Converter combines multiple images into one PDF. Want quality, format and resizing together in one place? The Smart Image Compressor covers all of it.
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