Click to choose, or drop an image here
You can also paste with Ctrl+V · select several at once · dropping anywhere on the page works
PNG / JPEG / WEBP / BMP / GIF / SVG / AVIF / TIFF / ICO / APNG / HEIC / HEIF, as many at a time as you like, up to 20 MB each. HEIC/HEIF (iPhone photos) is read by a decoder bundled with this page, so Chrome and Firefox convert it just as well as Safari. Images are processed in your own browser and never uploaded.
No image loaded yet
Output settings
Target format
Pick a target format - the result is recomputed as you go.
Only JPEG, WEBP, GIF and AVIF respond to quality: lower means a smaller file and more visible loss.
Leave empty or use 100 to keep the original size; give a width or height to scale proportionally.
Rotates clockwise; 90°/270° swaps width and height, and the output size is measured after the rotation.
Applies grayscale / black-and-white and friends to the pixels before encoding, for every output format. The alpha channel is left alone.
Stamps a line of text onto every image. The font size follows a percentage of the image width, so the look stays the same across different resolutions. Leave it empty for no watermark.
Converted result
Converting…Features
- Ten formats, any direction: PNG, JPEG, WEBP, BMP, GIF, SVG, AVIF, TIFF, ICO and APNG convert into each other, and all ten are accepted as input.
- Batch processing: select several files at once or drop in a whole folder, up to 50 images converted together. Each one shows its own status, click a thumbnail to inspect it, and grab every result as a single ZIP.
- Quality and size under control: set the encoder quality for JPEG, WEBP and AVIF, or the colour count for GIF, and watch the output size move against the original in real time.
- Transparency on your terms: keep the alpha channel when the format allows it, or flatten onto a colour you choose instead of being forced onto white.
- Rotate, flip and resize: rotate in 90° steps, flip horizontally or vertically; output dimensions are measured after the rotation and scale proportionally, and ICO output automatically carries 16 to 256 px sizes.
- Colour modes and text watermarks: grayscale, black & white, sepia and invert, none of which touch the alpha channel; the text watermark offers six placements (including a -20° tile) and sizes itself as a percentage of the image width, so it looks the same on images of any resolution.
- Entirely local: decoding, scaling, colour quantization and compression all run in your browser. There is no backend to call and nothing is uploaded, and the interface speaks English, 简体 and 繁體.
How to use
- Click the drop zone to pick several images at once, drag images (or a whole folder) anywhere onto the page, or paste with Ctrl+V.
- Choose a target format under Output settings, then drag the quality slider, rotate or flip, pick a colour mode and a fill colour for transparent areas, optionally add a watermark, and set the output width and height.
- Click a thumbnail in the list to inspect each result; download a single image on its own, or press Download all to get everything as one ZIP.
FAQ
- Are my images uploaded to a server?
- No. Every step - decode, scale, colour quantization, compression, packaging - is done by the browser's own Canvas API and the encoders bundled in this page. The page is fully static with no backend and no third-party API, so your image only ever exists in browser memory and leaves no trace in server logs.
- Why did my file get bigger after converting?
- Usually the format direction is backwards. A PNG photo converted to lossless PNG, or to uncompressed BMP, can only get bigger - PNG applies deflate internally while BMP applies no compression at all. Re-encoding an already-small JPEG with a high quality setting inflates it too. The right move is to send photos to JPEG, WEBP or AVIF at quality 70-85, and images with transparency to PNG or WEBP. If you want a smaller file without changing format, the image compression tool on this site does a much better job.
- Where does the transparent background go when I convert to JPEG?
- JPEG has no concept of transparency, so transparent pixels have to land on some concrete colour. Browsers default to white; this page exposes that step as the transparency fill setting. Fill in your page background colour for dark layouts, or red or blue for ID photos and e-commerce cutouts, and you avoid the ugly white or black fringe. BMP and TIFF behave the same way.
- What is the difference between GIF and APNG, and which should I pick?
- GIF is limited to 256 colours, so gradients and photographs band badly and pick up noise, but it has broad compatibility and usually a smaller file. APNG rides on PNG's chunks, keeps full 24-bit colour and per-frame transparency, and looks clearly better - at the cost of a larger file. Here the GIF quality slider controls the quantizer (lower means fewer colours and a smaller file), so try lowering quality first when GIF bands. Choose APNG when animation quality matters more than file size.
- My AVIF will not open, can I drop a HEIC photo straight in, and how do I actually use SVG and ICO?
- AVIF needs a fairly recent browser to decode; messaging apps, mail clients and older Windows builds often cannot display it, so target WEBP or JPEG there. HEIC is the format iPhone photos use. Safari reads it natively, while Chrome and Firefox still have no built-in decoder - so this page bundles a HEIF decoder of its own and loads it only when you actually drop in a .heic/.heif (about 680 KB gzipped). It then converts exactly like any other image, and Safari goes down that same path too, so the behaviour does not change from browser to browser. Decoding is local as well: your photos never leave the device. A few rarer HEIF features (some AVIF-in-HEIF and grid images, for example) this build cannot handle, and it says so plainly and suggests exporting a JPG. The SVG output here embeds the bitmap in a vector container (the viewBox matches the pixel size), which is the handy part - it scales cleanly with CSS - but it is a wrapper, not a trace: the bitmap gains no new detail, so redraw illustrations in a vector editor. The ICO writes 7 sizes (16, 24, 32, 48, 64, 128, 256 px) into one file, which browsers and Windows pick from automatically; rename it to favicon.ico and drop it in your site root.
About this tool
Image Format Converter is an online image format converter: one upload, any direction between PNG / JPEG / WEBP / BMP / GIF / SVG / AVIF / TIFF / ICO / APNG, with a quality slider, a transparency fill colour and output sizing - and a size comparison plus preview for the result.
PNG, JPEG, WEBP and AVIF are produced by the browser's own encoders; BMP, TIFF, ICO, SVG, APNG and GIF (frequency-based colour quantization + Floyd-Steinberg dithering + LZW compression) are written by encoders bundled in this page, with no third-party library. The page has no backend and no external API, and the interface speaks English / 简体 / 繁體.
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If what you need is a smaller file rather than a different format, use the image compression tool: it palette-quantizes PNG and re-encodes JPEG with mozjpeg, which beats plain format swapping by a wide margin.
Runs in your browser · nothing is uploaded · free · English / 中文