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Image Converter (PNG, JPG, WebP, AVIF, BMP, ICO, GIF)

Batch convert images between PNG, JPG, WebP, AVIF, BMP, ICO and GIF in your browser. Set quality, pick a background for transparent areas, keep file names and download everything as one ZIP.

Overview

Converts batches of images between PNG, JPG, WebP, AVIF, BMP, ICO and single-frame GIF in your browser. Drop up to 100 files, choose the target format and quality, set a background colour for transparent areas when the format has no alpha, and download each file or a ZIP of all of them. Files keep their names with the new extension.

How It Works

Drop images or click to browse; PNG, JPG, WebP, AVIF, GIF, BMP, ICO and SVG are read, plus HEIC in Safari. Pick the output format. JPG, WebP and AVIF show a quality slider; JPG always gets the background colour you choose, and BMP gets it unless you switch on 32-bit BMP with transparency. ICO asks which icon sizes to include, from 16 to 256 px. Click Convert, watch the progress bar or press Cancel, and the results table lists the before and after size of every file.

Step-by-Step Usage Guide

  1. Drop the images you want to convert, or click the drop area to pick them.
  2. Choose PNG, JPG, WebP, AVIF, BMP, ICO or GIF as the output format.
  3. Set quality for JPG, WebP or AVIF, and a background colour where transparency cannot be kept.
  4. Click Convert and wait for the progress bar, or press Cancel to stop.
  5. Download single files from the table or click Download all as ZIP.

Technical Specifications & Standards

Each file is decoded with createImageBitmap, which applies the EXIF orientation so photos come out upright, and drawn onto a canvas. PNG, JPG, WebP and AVIF are encoded by the browser's own canvas encoder, and the first bytes of every result are checked against the format's signature, because browsers that lack an encoder quietly return PNG instead of failing. That check is why AVIF is marked unsupported where it cannot be written, rather than producing a mislabelled file. BMP, ICO and GIF are written by code in this tool. BMP is either a 24-bit file with the classic 40-byte header and rows padded to 4 bytes, or a 32-bit BITMAPV4 file with an alpha channel mask. ICO wraps one PNG per chosen size in an icon directory, the PNG-in-ICO layout Windows has read since Vista. GIF goes through a median-cut quantizer and Floyd-Steinberg dithering to fit 256 colours. Very large images are scaled down to 50 megapixels, the most a canvas can safely hold, and EXIF metadata is not copied into the output.

Targeted Use Cases

  • Turning a folder of PNG screenshots into much smaller WebP files for a website.
  • Converting WebP images saved from the web into JPG for apps that cannot open WebP.
  • Building a multi-size .ico file from a square logo for a Windows app or favicon.
  • Producing BMP files for legacy software, embedded displays or old printers.
  • Testing how much smaller AVIF is than JPG for the same photos.

Notes & Gotchas

  • Use WebP or AVIF at 75 to 85 percent quality for photos on the web, and PNG for screenshots with text.
  • Pick the background colour to match the page the image will sit on when converting transparent PNGs to JPG.
  • Include 16, 32, 48 and 256 px in an ICO so Windows has a sharp size for every view.
  • Keep the original files: lossy formats lose detail each time they are re-encoded.

Frequently Asked Questions

Why is AVIF marked as not supported?

Writing AVIF needs an AVIF encoder in the browser's canvas. Chrome and Edge 121 or later and Firefox 130 or later have one; Safari can display AVIF but cannot encode it. The tool tests a tiny image first and only offers formats whose output really matches.

Are my images uploaded anywhere?

No. Decoding, conversion and ZIP packing all happen in this browser tab, and nothing is sent to a server. You can disconnect from the internet after the page loads and it still works.

What happens to transparency when I convert to JPG?

JPG cannot store transparency, so transparent areas are filled with the background colour you choose, white by default. PNG, WebP, AVIF, GIF, ICO and 32-bit BMP keep the alpha channel.

Can it convert animated GIFs?

Only the first frame is converted, because canvas decoding gives a single still image. To work with every frame, use the GIF Frame Splitter, and to build animations use the GIF Maker.

Is the EXIF data kept?

No. Pixels are re-encoded from a canvas, so camera, date and GPS metadata are dropped. Photos are decoded with their orientation applied first, so they still appear the right way up.

Related tools

  • HEIC to JPG Converter - Convert iPhone HEIC photos to JPG or PNG on your device using the browser's own decoder. Works in Safari, which can read HEIC; other browsers get a clear explanation instead of a fake result.
  • Image Compressor - Shrink JPEG and WebP file sizes with a quality slider and optional max-width. Preview the result and see exactly how many percent you saved.
  • Image Resizer - Resize images to exact pixel dimensions with aspect-ratio lock, and convert between PNG, JPEG, and WebP in one step.
  • SVG to PNG Converter - Render SVG code or files to PNG, JPG or WebP at any scale or exact size, with a transparent or solid background, entirely in your browser canvas.
  • PDF to JPG / PNG - Convert PDF pages to JPG or PNG images at up to 3x resolution, pick a page range and download all pages as a ZIP.
  • Image to PDF - Combine JPG and PNG images into a single PDF with page size, orientation, and margin controls. Fully offline.