Image converter tools

What you need to know

Image format conversion is the process of re-encoding an image from one file format to another. Each format uses a different compression algorithm, color model, and feature set, so conversion involves trade-offs between file size, visual quality, transparency support, and compatibility. The most common conversions are between PNG, JPG, WebP, and HEIC, each serving a different purpose. PNG excels at lossless graphics with transparency, JPG dominates photographic content with efficient lossy compression, WebP offers modern compression for web delivery, and HEIC provides superior efficiency on Apple devices. Understanding when to convert and which target format to choose prevents quality loss, unnecessary file bloat, and compatibility failures.

Key points

• Lossy formats discard data permanently and cannot be recovered by converting back
• Transparency is supported by PNG, WebP, and HEIC, never by standard JPG
• Converting between lossy formats repeatedly causes generational quality degradation
• Always keep the original source file when converting, especially for archival needs
• Browser-based conversion processes files locally without uploading, preserving privacy

Preparing screenshots for web publishing

PNG screenshots are often 2-5 times larger than equivalent JPG or WebP files. Converting to WebP for modern browsers or JPG for universal compatibility reduces page weight and improves load times without noticeable quality loss.

Making iPhone photos shareable

HEIC photos from iPhones are rejected by many websites and Windows apps. Converting them to JPG or WebP in the browser makes them viewable and uploadable everywhere without installing extra codec packs.

Recommended practices

• Convert to the target format only once, then compress or resize the converted file
• Use PNG when transparency or sharp text matters; use JPG or WebP for photographs
• Preview the output before downloading to catch quality issues early
• Keep the original file archived separately from converted copies
• Choose WebP when the target platform supports it for the smallest file sizes

Common mistakes to avoid

• Converting JPG to PNG expecting quality improvement: PNG is lossless, but it cannot recover detail already lost by JPG compression. The PNG file will simply be larger with identical visual quality.
• Forgetting that JPG does not support transparency: Converting a transparent PNG to JPG fills transparent areas with a solid color, which can ruin logos and graphics designed for transparent backgrounds.
• Repeatedly converting between lossy formats: Each JPG-to-JPG conversion applies a new round of lossy compression, progressively degrading quality. Always work from the original lossless source when possible.