The Short Answer
Use JPG for photographs. Use PNG when you need transparency or for screenshots and graphics. Use WebP for web images where file size matters. Use AVIF for next-generation compression when browser support is not a concern.
Now let's look at why.
JPG (JPEG) — The Photography Standard
JPG uses lossy compression, which means it throws away some image data to make the file smaller. For photographs with millions of natural colors and smooth gradients, this loss is nearly invisible — the human eye cannot tell the difference between a high-quality JPG and the original at normal viewing distances.
Best for: Photographs, product images, portraits, landscapes, any image with complex color gradients.
Avoid for: Text, line art, logos, screenshots, anything with hard edges or transparency needed.
A typical full-resolution photograph saved as JPG at 85% quality is usually between 200 KB and 2 MB — small enough to share by email or post on social media without delay.
PNG — Lossless and Transparent
PNG uses lossless compression, meaning every pixel is preserved exactly as it was. This makes PNG ideal for images where precision matters: logos with crisp edges, text overlays, icons, and screenshots where you need to read small print clearly.
PNG also supports a full alpha channel, which is technical language for "transparent background." This is why PNG is the standard for logos that need to sit on different background colors, and for stickers or overlays.
Best for: Logos, icons, screenshots, transparent backgrounds, graphics with text, line art.
Avoid for: Photographs (the files are much larger than JPG with no visible quality benefit).
A PNG photograph can be 5–10× larger than the same image as a JPG. For web pages with many images, this adds up quickly.
WebP — The Modern Web Format
WebP was developed by Google specifically for web performance. It offers both lossy and lossless compression modes and supports transparency — meaning it can replace both JPG and PNG in most web contexts while producing files that are typically 25–35% smaller.
Best for: Website images, e-commerce product photos, blog images, any image displayed in a modern browser.
Avoid for: Print (most print software does not support WebP), email attachments (some email clients do not display it), legacy systems.
Browser support for WebP is now over 97%, covering Chrome, Firefox, Safari (since 2020), and Edge. For most web projects, switching from JPG/PNG to WebP is one of the highest-impact performance improvements you can make.
AVIF — Next-Generation Compression
AVIF is the newest mainstream image format, derived from the AV1 video codec. It compresses images even more efficiently than WebP — typically 30–50% smaller than JPG at equivalent quality — while supporting HDR, wide color gamut, and transparency.
Best for: Cutting-edge web performance, large image galleries, streaming platforms.
Avoid for: Wide compatibility requirements (older browsers and many software tools still do not support it).
Quick Comparison Table
| Format | Transparency | Compression | Best Use |
|---|---|---|---|
| JPG | No | Lossy (small) | Photos |
| PNG | Yes | Lossless (large) | Logos, screenshots |
| WebP | Yes | Both (small) | Web images |
| AVIF | Yes | Both (smallest) | Modern web |
| GIF | Yes (1-bit) | Lossless (medium) | Simple animations |
| SVG | Yes | Vector (tiny) | Icons, logos |
Converting Between Formats
You can convert between any of these formats using the ILoveConvert image converter. Upload your image, select the output format, and download the result. For JPG and WebP, a quality setting of 85–90% gives the best balance of size and visual quality.
The One Rule to Remember
Never convert a JPG to PNG expecting to "upgrade" it. JPG lossy compression is permanent — once the data is lost, making the file lossless again (PNG) just makes a larger file with the same quality. Always start from the original high-quality source when changing formats.