Image Format Converter

It is completely free with no account, no watermark and no file-count limit beyond the 60-file queue cap that keeps your browser responsive.

More importantly, it is a no-upload image converter. Every conversion runs inside your own browser using the HTML Canvas API, so your images never travel to a server and are never stored anywhere. You can verify this yourself: open your browser’s developer tools, switch to the Network tab, and convert a file — you will see no upload request. The tool even keeps working if you disconnect from the internet after the page has loaded. That makes it suitable for confidential screenshots, client work and personal photos.

Lossless compression rewrites the file more efficiently without discarding a single pixel value. Decode a lossless PNG and you get back the exact original data, which is why it is safe to re-save repeatedly. The trade-off is size: photographs contain too much fine detail to compress well losslessly.

Lossy compression permanently throws away information the human eye is least likely to notice — subtle colour variation and high-frequency detail. This is how JPEG, and WebP or AVIF in lossy mode, achieve dramatically smaller files. The catch is that the loss is cumulative: every re-save degrades the image a little further. Always keep a lossless master copy and export lossy versions from it, rather than re-compressing an already-compressed file.

No format gives you a direct ranking boost — but image weight strongly affects Largest Contentful Paint, which is one of Google’s Core Web Vitals and a confirmed page-experience signal. Smaller images mean faster rendering, which means better real-user metrics.

In practice: use WebP as your site-wide default, and AVIF with a fallback for large hero images where the extra saving is worth the complexity. Then reinforce it with the basics that matter just as much — descriptive alt text, correctly sized images rather than oversized ones scaled down in CSS, explicit width and height attributes to prevent layout shift, and loading="lazy" on anything below the fold.

Yes. Select or drag as many files as you need — the batch queue holds up to 60 images per session, with a 30 MB limit per file. Choose one output format and quality setting, press Convert All, and every file is processed in sequence.

Each row in the queue shows the original size, the converted size and the percentage change, so you can spot any file that grew instead of shrinking. When you are done, download images individually or use Download All as ZIP to get everything in one archive. Files that share a name are automatically numbered inside the ZIP so nothing is overwritten.

Almost, but not quite. AVIF is supported in Chrome 85+, Firefox 93+, Safari 16.4+ and Edge 121+, and reached Baseline availability in January 2024. Visitors on older browsers, some in-app webviews and certain email clients still cannot display it.

That is a display question. Separately, this converter can only create AVIF files if your own browser includes an AVIF encoder — and browser encoding support lags behind decoding support. If the AVIF button is greyed out with a notice above the converter, your browser can probably view AVIF but cannot write it; try the latest Chrome or Edge. For anything published publicly, serve AVIF inside a <picture> element with a WebP or JPEG source as fallback.

Set the quality slider to 100. At maximum quality the WebP encoder preserves detail so closely that the result is visually indistinguishable from the source, while still producing a smaller file than the original PNG in most cases.

Be aware of one technical nuance: the Canvas API used by browser-based converters always writes lossy WebP, even at quality 100 — it does not expose the lossless WebP mode. For screenshots, logos and line art where absolute pixel fidelity is required, keep the PNG. For photographs and rich illustrations, WebP at quality 90–100 is effectively lossless to the eye at a fraction of the size.

This is normal in three situations, and the queue will show it as a positive percentage so you can catch it immediately.

First, converting a lossy file to PNG: a JPEG photo re-encoded as lossless PNG can easily triple in size, because PNG must store every JPEG artefact faithfully. Second, converting flat graphics to a lossy format: a two-colour logo compresses beautifully in PNG and poorly in JPEG. Third, a quality setting that is too high — WebP at quality 100 can exceed a well-optimised JPEG. If the output grows, either lower the quality or keep the original format.

JPEG has no alpha channel, so transparency cannot be preserved. Many converters render transparent pixels as black, which ruins logos and cut-out product shots.

This tool composites transparent areas onto a white background instead, which matches what most websites and documents expect. If you need to keep the transparent background, convert to PNG or WebP — both support a full alpha channel. AVIF supports transparency as well.

Pixel dimensions are preserved exactly — a 4000 × 3000 photo converts to a 4000 × 3000 file in the new format. This tool converts format only; it does not resize or crop.

Metadata behaves differently. Because conversion happens by redrawing the image onto a canvas, EXIF data such as camera model, GPS coordinates, capture date and embedded colour profiles is stripped from the output. That is a privacy advantage when publishing photos online — location data will not leak — but if you rely on EXIF for cataloguing, archive the original file before converting.