⚡ TL;DR — Quick reference
JPG (Joint Photographic Experts Group) has been the dominant photo format since the 1990s and is still the most widely supported format across every device, platform and application on the planet. It uses lossy compression — meaning some image data is permanently discarded to reduce file size — but at quality settings above 70%, the loss is invisible to the human eye in photographs.
- ✓Sharing photos on social media
- ✓Adding hero or background images to a webpage
- ✓Sending photos by email
- ✓Compatibility with older software matters
- ✓Transparency is not needed
- ✗The image has text, sharp lines or a logo
- ✗You need a transparent background
- ✗You will be editing and re-saving repeatedly
- ✗You want the absolute smallest file size
⚠️ Re-saving trap: Every time you open and re-save a JPG, it recompresses — losing a little more quality each time. Always keep a master copy in a lossless format (PNG or TIFF) and export JPGs from that.
PNG (Portable Network Graphics) uses lossless compression — no quality is ever discarded. This makes it ideal for images where sharpness and pixel-perfect accuracy matter: logos, UI screenshots, diagrams, and anything with text. PNG also supports full alpha-channel transparency, which JPG does not.
The downside is file size. A PNG of a photograph will almost always be dramatically larger than a JPG of the same image at equivalent visual quality — often 3× to 5× larger. This is why using PNG for photographs is one of the most common performance mistakes on the web.
- ✓You need a transparent background
- ✓The image contains text or sharp edges
- ✓It is a logo, icon, or UI screenshot
- ✓Lossless quality is required
- ✓You will edit the image further
- ✗The image is a photograph
- ✗File size is a concern
- ✗You are uploading to social media
- ✗You want next-gen format efficiency
💡 Quick fix: If someone sends you a PNG of a photograph (not a logo), convert it to JPG or WebP before publishing. You will typically reduce the file size by 60–80% with no visible difference.
WebP was developed by Google and released in 2010. It supports both lossy and lossless compression, transparency, and animation — making it a single format that can replace JPG, PNG, and GIF simultaneously. At equivalent visual quality, WebP files are typically 25–35% smaller than JPG and 20–30% smaller than PNG.
Browser support is now excellent — Chrome, Firefox, Safari (since 2020), Edge, and Opera all support WebP natively. For most new websites, WebP should be your default format for all images.
- ✓Serving images on a modern website
- ✓You want smaller files than JPG or PNG
- ✓You need transparency (replaces PNG)
- ✓You need simple animation (replaces GIF)
- ✓Your audience uses modern browsers
- ✗Sending to someone who may open in older software
- ✗Uploading to platforms that reject WebP (some CMSs)
- ✗You need maximum compression (use AVIF instead)
- ✗Printing — use TIFF or PDF instead
💡 WordPress note: WordPress has supported WebP uploads since version 5.8. If you are on an older theme or plugin stack, test WebP images before migrating your entire media library.
AVIF (AV1 Image File Format) is the newest major image format, derived from the AV1 video codec. It offers the best compression of any format currently available — typically 40–50% smaller than JPG and 20% smaller than WebP at equivalent perceptual quality. It also supports HDR, wide color gamut, and transparency.
The trade-off is browser support, which is good but not universal (Chrome, Firefox, and Safari 16+ support it, but older browsers do not), and encoding speed, which can be slow for large images. For most new projects, using AVIF with a WebP fallback is the optimal approach.
- ✓Absolute smallest file size is the priority
- ✓You are building a performance-optimized site
- ✓Your audience uses modern browsers (2021+)
- ✓You have a WebP fallback in place
- ✗You need broad legacy browser support
- ✗Fast encoding speed matters
- ✗Uploading to social platforms (usually unsupported)
- ✗Your CMS does not handle it yet
What About GIF and SVG?
GIF is a 1987 format limited to 256 colors. Its only remaining use case is short looping animations — memes, reaction clips, loading spinners. For anything over 3 seconds, a silent MP4 video is a dramatically better choice: smaller file, better quality, more color depth. Most modern platforms (Slack, Twitter, Discord) convert GIF uploads to video automatically behind the scenes.
SVG (Scalable Vector Graphics) is not a raster format like the others — it stores shapes as mathematical instructions rather than pixels. This means SVG files are resolution-independent: they look perfectly sharp at any size, from a 16px favicon to a 4K display. File sizes for logos and icons in SVG are typically tiny (1–20kB). Use SVG for all icons, logos, and illustrations. You cannot use SVG for photographs.
Full Format Comparison Table
| Format | Compression | Transparency | Animation | Browser support | Relative size |
|---|---|---|---|---|---|
| JPG | Lossy | ❌ | ❌ | Universal | ●●●○○ |
| PNG | Lossless | ✅ | ❌ | Universal | ●●●●○ |
| WebP | Both | ✅ | ✅ | Excellent | ●●○○○ |
| AVIF | Both | ✅ | ✅ | Good | ●○○○○ |
| GIF | Lossless | ✅ (1-bit) | ✅ | Universal | ●●●●● |
| SVG | Vector | ✅ | ✅ | Universal | ●○○○○ |
Relative size: ●○○○○ = smallest, ●●●●● = largest (for equivalent visual quality)
How to Choose — A Simple Decision Guide
Run through these questions in order to pick the right format every time:
→ Use SVG if it is vector art. Use PNG if it is a raster file with transparency.
→ Use WebP (first choice) or PNG (fallback). Never JPG.
→ Use AVIF (with WebP fallback) or WebP. Only use JPG if you need maximum compatibility.
→ Use JPG for photos. PNG for graphics. Most platforms recompress on upload anyway.
→ Under 3 seconds: WebP or GIF. Over 3 seconds: use a silent MP4 video instead.
→ Use TIFF or PDF (300 DPI). Web formats like JPG and PNG are for screens, not print.
How to Convert Between Formats
If you have an image in the wrong format, you can convert it without any software using the FlexoTools Image Compressor. Upload your image, then use the Output Format dropdown to select the target format — WebP, AVIF, JPG, or PNG. The tool handles the conversion and compression in one step, entirely in your browser.
Use for any PNG photograph that has no transparency
Best default upgrade for existing web image libraries
Maximum compression for performance-critical pages
Convert or compress your image now
Free, no signup, works in your browser. JPG, PNG, WebP and AVIF supported.
🖼️ Open Image Compressor