JPEG, PNG, WebP, HEIC, AVIF — with so many image formats, it is easy to wonder which one to use. This guide covers every major image format, comparing compression methods, quality, and browser support. It includes use-case recommendations so you will never second-guess your format choice again.
What Are Image Formats?
An image format is a standard for saving digital image data as a file. Different formats offer different compression methods, color depth, transparency support, and file sizes — making it important to choose the right one for your purpose.
Image formats fall into two compression categories:
| Compression Type | How It Works | Common Formats |
|---|---|---|
| Lossy | Discards information invisible to the eye for much smaller files. Irreversible | JPEG, WebP (lossy), AVIF (lossy) |
| Lossless | Compresses without any quality loss. Fully reversible | PNG, WebP (lossless), AVIF (lossless), GIF |
JPEG — The Standard for Photos
JPEG (Joint Photographic Experts Group) was established in 1992 and has been the standard format for photographs for over 30 years.
JPEG at a Glance
| Feature | Details |
|---|---|
| Compression | Lossy (DCT-based) |
| Color depth | About 16.7 million colors (24-bit) |
| Transparency | Not supported |
| Animation | Not supported |
| File size | Small (optimized for photos) |
| Compatibility | Supported by virtually all devices and apps |
When JPEG Excels
Photos and gradients with smooth color transitions. JPEG compresses areas where neighboring pixels are similar, achieving dramatic size reduction with barely noticeable quality loss.
JPEG Limitations
- Quality degrades with each re-save. Edit in a lossless format and export to JPEG only at the final step
- No transparency support. Use PNG when you need transparent backgrounds
- Poor with solid colors and text. Sharp edges develop mosquito noise (blurring artifacts)
Free Tool
Image Compressor
Compress JPEG, PNG, WebP, and HEIC images. Adjust quality, remove Exif data, and convert formats.
Try it now →PNG — Lossless Compression for Illustrations
PNG (Portable Network Graphics) was established in 1996. Its defining features are lossless compression and transparency support.
PNG at a Glance
| Feature | Details |
|---|---|
| Compression | Lossless (Deflate) |
| Color depth | About 16.7 million colors + alpha channel |
| Transparency | Supported (including semi-transparency) |
| Animation | Supported via APNG |
| File size | Larger than JPEG for photos |
| Compatibility | Supported by virtually all devices and apps |
When PNG Excels
Illustrations, logos, diagrams, and screenshots — images with sharp color boundaries and large solid-color areas. Lossless compression keeps text and lines perfectly crisp.
PNG Limitations
- Not ideal for photos. Same photo saved as PNG can be 3-5x larger than JPEG
- Large file sizes. Consider WebP conversion when using many PNGs on a website
Free Tool
PNG ⇔ JPG Converter
Convert between PNG and JPG formats. Adjust quality and handle transparent backgrounds.
Try it now →WebP — Optimized for the Web
WebP was developed by Google in 2010 and combines the best of JPEG and PNG, optimized for web display.
WebP at a Glance
| Feature | Details |
|---|---|
| Compression | Both lossy and lossless |
| Color depth | About 16.7 million colors + alpha channel |
| Transparency | Supported (even in lossy mode) |
| Animation | Supported (GIF alternative) |
| File size | About 25-35% smaller than JPEG |
| Compatibility | All major browsers supported (except IE) |
WebP Advantages
- 25-35% smaller than JPEG in lossy mode
- 26% smaller than PNG in lossless mode
- Supports both transparency and animation, potentially replacing PNG, GIF, and JPEG
- Supported by Chrome, Safari, Firefox, and Edge
WebP Limitations
- Older browsers (IE) cannot display it. As of 2026, IE usage is near zero
- Some image editing software does not support it. Photoshop added support in 2022
- Some social platforms do not accept it (may convert to JPEG on upload)
Free Tool
WebP Converter
Convert images to WebP or WebP to JPG/PNG. Reduce file size with modern web-optimized format.
Try it now →HEIC — iPhone Default Format
HEIC (High Efficiency Image Container) became iPhone's default image format with iOS 11 in 2017.
HEIC at a Glance
| Feature | Details |
|---|---|
| Compression | HEVC (H.265)-based lossy |
| Color depth | Up to 16-bit (about 281 trillion colors) |
| Transparency | Supported |
| Animation | Supported |
| File size | About 50% of JPEG at equivalent quality |
| Compatibility | Native on Apple devices; limited on Windows/Android |
HEIC Advantages
- Half the file size of JPEG at the same quality
- 16-bit color for richer color representation than JPEG's 8-bit
- Multiple images in one file, used for Burst photos and Live Photos
HEIC Compatibility Challenges
HEIC is technically superior, but compatibility issues frequently require conversion:
- Some Windows apps cannot open HEIC files
- Many web services only accept JPG/PNG
- Photo print services often do not support HEIC
- Android users may not be able to open HEIC files
Free Tool
HEIC to JPG/PNG/WebP Converter
Convert iPhone HEIC photos to JPG, PNG, or WebP. Batch conversion with quality control.
Try it now →AVIF — Maximum Compression Efficiency
AVIF (AV1 Image File Format) was introduced in 2019, applying video codec AV1 technology to images for the highest compression efficiency of any current format.
AVIF at a Glance
| Feature | Details |
|---|---|
| Compression | AV1-based lossy and lossless |
| Color depth | Up to 12-bit (HDR support) |
| Transparency | Supported |
| Animation | Supported |
| File size | About 50% smaller than JPEG, about 20% smaller than WebP |
| Compatibility | Chrome, Firefox, Safari (16.4+) |
AVIF Advantages
- About 50% smaller than JPEG, about 20% smaller than WebP
- HDR support for wider dynamic range
- Royalty-free (unlike HEIC's HEVC patents)
- Handles both photos and illustrations well
AVIF Limitations
- Encoding is slow compared to JPEG and WebP
- Not supported in Safari older than 16.4 or older Edge. Fallback images needed
- Limited image editor support
- Especially slow for high-resolution images
Full Comparison Table
| Feature | JPEG | PNG | WebP | HEIC | AVIF |
|---|---|---|---|---|---|
| Year | 1992 | 1996 | 2010 | 2015 | 2019 |
| Compression | Lossy | Lossless | Both | Lossy | Both |
| Transparency | No | Yes | Yes | Yes | Yes |
| Animation | No | Limited (APNG) | Yes | Yes | Yes |
| File size | Medium | Large | Small | Small | Smallest |
| Browser support | Excellent | Excellent | Good | Limited | Good |
| Editor support | Excellent | Excellent | Good | Limited | Limited |
Recommended Formats by Use Case
Web
| Scenario | Best Format | Why |
|---|---|---|
| Website photos | WebP (JPEG fallback) | Lightweight, nearly universal browser support |
| Logos and icons | SVG or PNG | Vector for SVG, raster for PNG |
| OGP images | JPEG | Reliable across all social platforms |
| GIF replacement | WebP (or MP4) | Much smaller than GIF |
| Maximum compression | AVIF (with fallback) | Smallest possible file size |
Everyday
| Scenario | Best Format | Why |
|---|---|---|
| Email photos | JPEG | Small enough for attachment limits, universal |
| Social media | JPEG | Uploads reliably on every platform |
| Screenshots | PNG | Text and UI details stay sharp |
| iPhone storage | HEIC (as-is) | Saves space, high quality |
| Sharing iPhone photos | Convert to JPG | Ensures compatibility |
| Scenario | Best Format | Why |
|---|---|---|
| Photo prints | JPEG (high quality) | Most print services support it |
| Logo/diagram prints | PNG | Preserves sharp edges |
| Professional printing | Service-specified (PSD/AI) | JPEG and PNG are mainly for office use |
Free Tool
Image Compressor
Compress JPEG, PNG, WebP, and HEIC images. Adjust quality, remove Exif data, and convert formats.
Try it now →How to Convert Between Formats
sakutto's online tools let you convert image formats right in your browser — no installation needed, and files are never sent to any server.
- JPEG and PNG: Use the JPG/PNG conversion tool
- WebP conversion: Convert from JPEG/PNG to WebP
- HEIC to JPG: Convert iPhone photos to JPG
- Image compression: Reduce file size in any format
FAQ
Which image format should I use?
It depends on the use case. JPEG or WebP for photos, PNG for illustrations and logos, HEIC for iPhone storage (convert to JPG for sharing), and AVIF for cutting-edge web optimization. When in doubt, JPEG works almost everywhere.
Is WebP or AVIF better?
AVIF offers superior compression efficiency, but WebP has broader browser support and faster encoding. WebP is the practical choice today, while AVIF is likely to become mainstream as support expands.
How do I open HEIC photos on Windows?
Windows 11 has native support, though some apps may not open HEIC files. Use an online HEIC-to-JPG converter to convert in your browser without uploading files to any server.
Are my files uploaded to a server during conversion?
sakutto's image tools process everything in your browser. Your files are never sent over the internet, so it is safe for private and confidential images.
Are JPEG and JPG different?
No, they are exactly the same format. JPEG is the official name, but older Windows systems limited extensions to 3 characters, creating the .jpg shorthand. There is no difference in quality or file size.
Summary
Each image format has its strengths, and choosing the right one for the job makes all the difference. JPEG for photos, PNG for illustrations, WebP for web optimization, HEIC for iPhone storage, AVIF for maximum compression — with these basics, you will never struggle with format selection again. When you need to compress or convert, sakutto's online tools handle it all right in your browser.
Free Tool
Image Compressor
Compress JPEG, PNG, WebP, and HEIC images. Adjust quality, remove Exif data, and convert formats.
Try it now →