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Image Format Converter

Media

Drag images here or paste from the clipboard. Reads JPEG, PNG, WebP, GIF, AVIF, HEIC, BMP, ICO, TIFF, SVG and JPEG XL (where your browser can). Up to 50 files, 25 MB each (100 MB for TIFF and BMP).

Everything happens in your browser. Your files are never uploaded; the HEIC decoder, TIFF codec and GIF encoder are code this page downloads the first time a file needs them.

Convert to
Higher keeps more detail and makes a larger file.

#FFFFFF

Writes back only the capture date, time-zone offset and camera model so photo apps keep sorting by date. GPS and all other metadata are always removed.

About This Tool

Image Format Converter – change the format, see the trade-offs

This image format converter turns the files that phones, cameras, scanners and websites produce into the format you actually need. Drop in a batch of HEIC, JPEG, PNG, WebP, GIF, AVIF, BMP, ICO, TIFF or SVG files, choose one output (JPEG, PNG, WebP, GIF, BMP, TIFF or ICO) and download the results one at a time or as a ZIP. Typical jobs are HEIC to JPG for iPhone photos, WebP to PNG for an editor that can't open WebP, PNG to ICO for a Windows shortcut, and SVG to PNG for a slide deck.

Every file is identified from its bytes rather than its extension, because a PNG renamed to .jpg or a HEIC with no type at all is common. Decoding and encoding run entirely in your browser, so this is a private image converter: the pictures never leave your device.

What each format can store

FormatCompressionTransparencyAnimationColoursRead hereWrite here
JPEGLossyNoNo16.7 millionYesYes
PNGLosslessFullAPNG (first frame here)16.7 millionYesYes
WebPLossy or losslessFullYes (first frame here)16.7 millionYesWhere the browser can
GIFLossless, 256-colour paletteOn/offYes (first frame here)256YesYes
BMPNone32-bit onlyNo16.7 millionYesYes
TIFFNone when written hereFullMulti-page (page 1 here)16.7 millionYesYes
ICOPNG insideFullNo16.7 millionYesYes
HEIC / AVIFLossyFullSequences (primary image here)Over 1 billionYesNo
SVGVectorFullNoAnyYes (rasterised)No

Which format should you pick?

  • Photos: JPEG or WebP. Both are lossy, which is what keeps a 12-megapixel photo at a couple of megabytes instead of 36.
  • Screenshots, logos and text: PNG. Lossless compression keeps hard edges crisp, where JPEG would add ringing around every letter.
  • Anything that needs transparency: PNG or WebP. JPEG has no alpha channel, so transparent areas are filled with the background colour you choose.
  • Windows icons: ICO, with several sizes (16, 32, 48 and 256 px by default) packed into one file. For a full website favicon set, use the dedicated favicon generator instead.
  • Printing and archiving: TIFF. It is uncompressed here, so it is large but accepted by virtually every print and archive workflow.

See the cost before you download

Each row lists what the conversion loses: flattened transparency, dropped animation frames, a 256-colour palette, removed metadata, a converted colour profile, or a vector image becoming pixels. The before/after view shows the real encoded output, not the canvas it came from, so compression artefacts are visible at 200% or 400%. Zoom to detail jumps to the busiest part of the picture, where artefacts appear first.

The format comparison encodes the selected image in every format and charts the actual file sizes against the original. Uncompressed sizes follow exact formulas: a 24-bit BMP is 54 + rowBytes × height bytes, with each row padded to a multiple of 4, and a TIFF written here is 1000 + 4 × width × height bytes. For a 1920 × 1080 image that is 6.2 MB and 8.3 MB, whatever the picture shows.

Converting to PNG doesn't add quality
A JPEG has already discarded detail. Saving it as PNG keeps the remaining pixels exactly, artefacts included, and usually makes the file several times larger. Convert to a lossless format to stop further loss, not to undo it.

How GIF output works

If the image already uses no more colours than the limit, GIF output uses those exact colours and is pixel-identical, so pixel art survives untouched. Otherwise the colours are reduced to a 256-entry palette and, with dithering on, the error is spread to neighbouring pixels (Floyd–Steinberg) so gradients band less. GIF transparency is on/off only: pixels below the threshold become transparent and soft edges are blended onto the background colour.

Metadata and dates

Re-encoding removes EXIF, XMP and IPTC data, including GPS location, which makes the output safer to share. For JPEG output, “Keep date taken & camera” writes back only the capture date, its time-zone offset and the camera make and model, so photo libraries still sort the picture correctly.

Very large photos
Some browsers, especially on iPhone and iPad, can't draw images above about 16.7 megapixels. When that happens the row offers a slightly smaller size at the same aspect ratio. The tool never shrinks an image without asking.

Credits

HEIC files are decoded, when the browser can't do it itself, with libheif and libde265 via libheif-js (LGPL-3.0), loaded unmodified as a separate file. TIFF files are read and written with UTIF.js (MIT), and GIF files are encoded with gifenc (MIT).

Frequently Asked Questions

Is the Image Format Converter free?

Yes, Image Format Converter is totally free :)

Can I use the Image Format Converter offline?

Yes, you can install the webapp as PWA.

Is it safe to use Image Format Converter?

Yes, any data related to Image Format Converter only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does this converter work, and are my photos uploaded?

No. Each file is identified from its bytes, decoded and re-encoded by your own browser, so the photos never leave your device. The only network traffic is the browser fetching this site's own code the first time it needs the HEIC decoder, the TIFF codec or the GIF encoder. After that, conversions keep working offline.

Does converting a JPG to PNG improve its quality?

No. JPEG compression throws detail away when the photo is saved, and PNG can only store the pixels that are left, artefacts included. The PNG is lossless from this point on, so it won't get worse with further edits, but it will usually be several times larger than the JPEG.

Why can't I convert to HEIC, AVIF or JPEG XL?

Browsers can read these formats but their canvas can't write them, so creating one needs an encoder compiled to WebAssembly. Those encoders are several megabytes and slow on phones, so this tool writes JPEG, PNG, WebP, GIF, BMP, TIFF and ICO instead. For small, high-quality web images, WebP is the closest alternative.

Why are my BMP and TIFF files so large?

Both are written uncompressed: 3 bytes per pixel for a 24-bit BMP and 4 bytes per pixel for a 32-bit BMP or a TIFF with transparency. A 12-megapixel photo therefore becomes about 36 to 48 MB, which is often 10 to 20 times the size of the JPEG. Use the size comparison to see the real numbers for your image before you download.

What happens to transparency, and why does my GIF look grainy?

PNG, WebP, TIFF, ICO and 32-bit BMP keep transparency. JPEG and 24-bit BMP fill transparent areas with the background colour you choose. GIF can only make a pixel fully transparent or fully opaque, and it holds at most 256 colours, so photos are dithered: their colours are mixed as fine dot patterns, which looks grainy close up.

Will my photo keep its date taken?

Re-encoding removes all metadata by default, including GPS location. For JPEG output you can turn on 'Keep date taken & camera', which writes back only the original capture date, time-zone offset and camera make and model so photo apps still sort the picture correctly. GPS and everything else stays removed.