What is Image Format Conversion?
Image format conversion transforms an image from one file format to another. Each format has its strengths: JPEG is ideal for photos, PNG supports transparency, WebP offers excellent compression, and AVIF is the most modern format with the best quality per kilobyte.
Choosing the right format directly affects file size, image quality, and compatibility. Saving a photo as PNG creates unnecessarily large files, while saving a logo as JPEG loses its sharp edges.
Formidex converts images entirely in the browser between PNG, JPEG, WebP, and AVIF formats. You see an instant preview of the result and can adjust quality settings before downloading.
How does Image Format Conversion work?
The image is first loaded into memory and decoded. Then it is re-encoded in the chosen target format using the Canvas API. Different options are available depending on the format: JPEG and WebP allow quality settings, while PNG always works losslessly.
When converting from formats with transparency (PNG, WebP) to formats without transparency support (JPEG), transparent areas are replaced with a white background. Keep this in mind if your image contains transparent areas.
Tips for best results
Use JPEG for photos and images with many colors and gradients. The format is universally compatible and creates small files. However, JPEG does not support transparency and each re-save slightly degrades quality.
PNG is suited for graphics with sharp edges, text, screenshots, and images needing transparency. Files are larger than JPEG, but compression is lossless.
WebP is the best all-rounder for modern websites. It combines the advantages of JPEG (small files) and PNG (transparency) in one format. AVIF goes a step further with even smaller files at the same quality, but is not supported by older browsers.
Common use cases
Website optimization: converting old JPEG and PNG images to WebP can reduce file size by 30 percent or more without visible quality loss. This noticeably speeds up loading times.
Add or remove transparency: convert a logo with transparent background (PNG) to JPEG for print, or vice versa convert a photo to PNG for use as an overlay.
Ensure compatibility: some platforms only accept certain formats. Social media sites often prefer JPEG, while print services frequently require PNG or TIFF. Conversion lets you quickly adapt your images to specific requirements.