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Image Converter

Choose the target format first, then drop images to convert them in bulk. Tune quality per format, use lossless WebP, set a background for transparency and name the output files — nothing is uploaded.

On-device・No upload

Your files and input are processed only inside your browser on this device and are never uploaded to our servers.

1Choose the target format

2WebP settings

82

75–85 is typical; smaller than JPEG at the same look.

Keeps every pixel identical. Ideal for shrinking PNG logos, diagrams and screenshots.

Example: IMG_0001.webp

{name}=original name, {w}{h}=width/height, {n}/{nn}/{nnn}=sequence, {fmt}=format. The extension is added automatically.

3Add images

Drop files here (multiple allowed)

or

Images are converted in this browser on your device and never uploaded.Accepts: JPEG / PNG / WebP / AVIF / GIF / BMP / HEIC (*)Up to 50 MB per filePaste (Ctrl+V) also works
Which format should I use?
FormatTransparencyQualityTypical sizeSupportBest for
JPEGNoLossyBaseline (100%)EverywherePhotos, email attachments, print shops, older software
PNGYesLosslessPhotos 3–10×EverywhereScreenshots, diagrams, logos, transparent assets, editing masters
WebPYesLossy / lossless≈ 65–75%Major browsers, recent OSesWebsite and blog images (the safe default)
AVIFYesLossy≈ 40–55%Recent browsers (not older systems)Speed-critical websites, large photos

Typical sizes compare an average photo saved at a similar visual quality; actual results depend on the image.

How to use

  1. Under “Choose the target format”, pick JPEG, PNG, WebP or AVIF. If unsure, see the “Which format should I use?” table.

  2. Adjust quality, lossless mode, background or size for that format, and optionally set a naming rule (e.g. {name}_{w}x{h}).

  3. Drop images or click “Choose files” (multiple files and Ctrl+V paste supported). Conversion starts immediately.

  4. Check the format, size and pixel dimensions in the list, and use “Compare” to inspect before and after.

  5. Download images one by one or as a ZIP, optionally with a report.csv.

What it does

Format-first workflow

Pick the target format first and see only the settings that matter: quality and background for JPEG, quality or lossless for WebP, optimisation effort for PNG, quality for AVIF.

Warnings before you convert

Transparency turning white in JPEG, photos ballooning as PNG, same-format re-compression — pitfalls are detected from the files you add and explained up front.

Lossless WebP

Convert to WebP without changing a single pixel — ideal for shrinking PNG logos, diagrams and screenshots with zero visual change.

Naming rules and a report

Name outputs in bulk with {name}, {w}, {h} and {nnn} tokens. The ZIP can include a report.csv with formats, sizes and dimensions before and after.

Quality encoders in the browser

MozJPEG, libwebp, libavif and OxiPNG run as WebAssembly in background Web Workers, and you can stop at any time.

Use cases

  • Turn PNG screenshots and assets into WebP to speed up a website
  • Convert WebP images back to JPEG/PNG for older software or print shops
  • Make iPhone HEIC photos open on Windows or business systems (using Safari)
  • Convert a batch of photos to AVIF for the fastest possible pages
  • Turn a transparent PNG logo into a JPEG on a white background for slides

Supported formats

Input

JPEG (.jpg / .jpeg / .jfif)PNGWebPAVIFGIF (still)BMPHEIC / HEIF (supported browsers such as Safari only)

Output

JPEGPNG (lossless)WebP (lossy or lossless)AVIF

Capability matrix

FeatureSupportNotes
Convert between JPEG, PNG, WebP and AVIFSupported—
Per-format quality, lossless WebP, PNG effortSupported—
Background colour for transparency (JPEG output)Supported—
Shrink by long edge (never upscales)SupportedFor precise resizing use Batch Resize & Convert
Naming rules, ZIP download, report.csvSupportedUp to 200 files, 50 MB each
Read HEIC (iPhone photos)PartialOnly in browsers that can display HEIC, such as Safari on Mac/iPhone
Read GIF and BMPPartialGIF as a still image only; animated GIFs are skipped
Convert animations (GIF / APNG / animated WebP)Not supported—
Output ICO, SVG, TIFF or PDFNot supportedICO belongs to the favicon generator
Carry over EXIF and colour profilesNot supportedOrientation is applied, metadata removed, output is sRGB

Limits & notes

  • Up to 50 MB per file, 200 files per batch and 100 megapixels per image.
  • Whether HEIC can be read depends on the browser; Chrome, Edge and Firefox usually cannot.
  • AVIF encoding takes seconds to tens of seconds per image.
  • Transparent areas become the chosen background colour when converting to JPEG.
  • EXIF (date, location…) and colour profiles are not carried over; output is sRGB with orientation applied to the pixels.

Privacy & safety

Reading, converting and zipping all happen inside your browser. Images are never sent to or stored on a server. Only the conversion engine (WebAssembly) is downloaded the first time.

FAQ

What changes when I convert PNG to JPEG?
JPEG cannot store transparency, so transparent areas are filled with the background colour (white by default). JPEG is also lossy, so text and line edges may soften slightly. Choose WebP or AVIF to keep transparency.
Should I convert to WebP or AVIF?
If unsure, WebP: it displays in virtually every current browser and encodes quickly. AVIF is smaller still, but slower to encode and unsupported by some older systems and apps.
Can I convert HEIC (iPhone photos) to JPEG?
Yes, in browsers that can display HEIC, such as Safari on Mac or iPhone. Chrome, Edge and Firefox usually cannot read HEIC; you’ll see an error explaining why and what to do.
Does converting JPEG to PNG improve quality?
No. Lost detail can’t be restored; the file just gets several times larger. Except for editing masters, keep photos as JPEG, WebP or AVIF.
How is this different from the Image Compressor?
This tool is about changing format, with per-format settings, warnings and naming rules. To shrink files while keeping their format, the Image Compressor is the better fit.

Related tools

Image Compressor

Drop images to shrink them in bulk while keeping them sharp. Convert to WebP or AVIF, resize, and compare before and after. Your images are never uploaded.

Image Target Size

Pick a limit like “under 200 KB” and get the best-looking JPEG or WebP that fits. Quality is lowered first; pixels are reduced only if that is not enough. Nothing is uploaded.

Icon Generator

From one image (or a letter or emoji), get favicon.ico, apple-touch-icon, Android/PWA icons, a maskable icon and an OGP image, plus the manifest and the <head> code to paste. Check blur at real size first — nothing leaves your browser.

Batch Image Resizer

Drop a batch of images and resize them by width, longest edge, box crop and more. Make several sizes (say 320, 640 and 1280) from each image in one go, then copy ready-made srcset HTML. Your images are never uploaded.

Crop, Pad & Canvas

Drag to crop, then rotate, straighten and add padding on one screen. Export straight to the recommended X header or Instagram size. Your image is never uploaded.

Image Editor

Annotate a screenshot or photo, reliably hide what must not be seen, tune the colours and export — on one screen. Made for how-to guides, bug reports and social posts. Your image is never uploaded and exports carry no metadata.

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