PictureEditor

Format Comparison Table

File Size Estimator

Upload an image to see estimated file sizes in each format. The tool converts your image using the Canvas API to generate real WebP, JPEG, and PNG sizes.

Visual Quality Comparison

Upload an image above to see a side-by-side quality comparison between JPEG (quality 60) and WebP (quality 60). Drag the slider to compare.

Which Format Should I Use?

Answer a few questions to find the best format for your use case.

JPEG — The Universal Standard

How JPEG Encoding Works

JPEG (Joint Photographic Experts Group) uses a multi-step lossy compression process. The image is first converted from RGB to YCbCr color space, separating brightness (luminance) from color (chrominance) information. The chrominance channels are typically downsampled to half resolution — called chroma subsampling (4:2:0) — exploiting the fact that human vision resolves brightness detail at much higher resolution than color detail. This single step reduces data by 50% with minimal visible impact.

Next, the image is divided into 8x8 pixel blocks, and each block undergoes a Discrete Cosine Transform (DCT) that converts spatial pixel values into frequency coefficients. Low-frequency coefficients represent gradual color changes; high-frequency coefficients represent fine detail and edges. The quantization step divides these coefficients by a quality-dependent matrix and rounds to integers, discarding high-frequency information that contributes little to perceived quality. Finally, Huffman entropy coding compresses the quantized coefficients into the final JPEG bitstream.

JPEG Strengths and Weaknesses

JPEG's primary strength is universal compatibility. Every device, browser, email client, and image viewer supports JPEG. Encoding and decoding are extremely fast due to decades of hardware optimization. For photographs at quality 80-90, JPEG produces excellent results. The weaknesses are the lack of transparency support, visible blocking artifacts at low quality settings (especially around text and sharp edges), and no lossless mode. JPEG also does not support animation.

WebP — The Recommended Default

WebP Architecture

WebP was developed by Google and released in 2010. Its lossy mode is based on VP8 video compression, using block prediction, Walsh-Hadamard transform, and advanced entropy coding (boolean arithmetic coding) that outperforms JPEG's Huffman coding. WebP divides images into macro blocks of 16x16 pixels with 4x4 sub-blocks, using intra-frame prediction from neighboring blocks to reduce redundancy before transformation and quantization.

WebP's lossless mode uses a completely different algorithm based on spatial prediction, color space transforms, backward reference coding, and Huffman entropy coding — similar to PNG but with additional techniques that consistently produce smaller files. WebP also supports alpha channels (transparency) in both lossy and lossless modes, and animated sequences using the WebP container format.

WebP vs JPEG: The Numbers

Across independent benchmarks, WebP lossy consistently produces files 25-35% smaller than JPEG at equivalent SSIM (structural similarity) quality scores. At quality 75 (a common web setting), a 1920x1080 photograph might be 350 KB as JPEG and 240 KB as WebP — a 31% reduction with no perceptible quality difference. WebP lossless typically produces files 26% smaller than PNG. With browser support at 99.4% globally in 2026, WebP should be your default format for all web images.

AVIF — Maximum Compression

The AV1 Advantage

AVIF (AV1 Image File Format) derives from the AV1 video codec developed by the Alliance for Open Media, which includes Google, Apple, Microsoft, Mozilla, Amazon, Netflix, and others. AV1 represents the state of the art in compression technology, using larger block sizes (up to 128x128), more prediction modes, and sophisticated loop filtering to achieve dramatic compression efficiency. AVIF inherits all of these advances for still images.

AVIF supports 8, 10, and 12-bit color depth, HDR (High Dynamic Range) with PQ and HLG transfer functions, wide color gamuts (BT.2020), film grain synthesis (encoding grain parameters rather than grain itself), and both lossy and lossless compression. It supports alpha transparency and can contain sequences for animation. The format specification is royalty-free, removing the licensing concerns that affected earlier formats like HEIC.

AVIF Trade-offs

AVIF's main limitation is encoding speed. Compressing a single image to AVIF takes 5-20x longer than WebP or JPEG, making it impractical for real-time client-side compression in this tool. Browser support reached 93% in early 2026, with Safari being the last major browser to add support. For production websites, the recommended approach is to use the HTML <picture> element to serve AVIF to supported browsers with WebP or JPEG as the fallback.

PNG — Lossless Precision

PNG Compression Mechanism

PNG (Portable Network Graphics) uses a two-stage lossless compression process. First, a filtering step predicts each pixel based on its neighbors and stores only the difference (residual). PNG supports five filter types: None, Sub, Up, Average, and Paeth. The optimal filter is chosen per row to minimize residual values. Second, the filtered data is compressed using DEFLATE (the same algorithm used in ZIP files), which combines LZ77 dictionary coding with Huffman entropy coding.

Because PNG is lossless, the decompressed output is bit-for-bit identical to the original. This makes PNG ideal for any workflow where the image will undergo further processing — editing, compositing, or format conversion. PNG supports 8-bit and 16-bit color depths, full 8-bit alpha transparency, and indexed color (palette mode) for images with few colors.

When PNG Wins

PNG is the optimal format for screenshots, UI mockups, technical diagrams, images with text overlays, logos, and any graphic with sharp edges and solid colors. A screenshot of a code editor might be 100 KB as PNG but 250 KB as JPEG — and the JPEG version will have visible artifacts around the text characters. PNG also excels for images that need transparency with crisp edges, such as logo overlays on varying backgrounds.

GIF and SVG

GIF — The Legacy Animation Format

GIF (Graphics Interchange Format) dates to 1987 and supports animation, which kept it relevant long after its technical limitations became apparent. GIF is limited to 256 colors per frame, uses LZW lossless compression (which is less efficient than DEFLATE or modern alternatives), and supports only 1-bit transparency (fully transparent or fully opaque — no semi-transparency). An animated GIF is typically 5-10x larger than the equivalent animated WebP or AVIF.

In 2026, GIF remains supported everywhere but should be avoided for new content creation. Animated WebP produces files 60-80% smaller with full 8-bit transparency and 24-bit color. For sharing animated content, most platforms now prefer short videos (MP4/WebM) over GIF, which are dramatically more efficient — a 10MB GIF might be 500KB as an MP4 at higher quality.

SVG — Scalable Vector Graphics

SVG is fundamentally different from all other formats discussed here because it is a vector format — it describes images as mathematical shapes, paths, and text rather than pixel grids. This means SVG files can scale to any resolution without quality loss, making them ideal for logos, icons, illustrations, charts, and any graphic that consists of distinct shapes rather than continuous photographic tones.

SVG files are XML-based text documents, which means they can be edited with a text editor, styled with CSS, animated with JavaScript or CSS animations, and indexed by search engines. A logo that is 50 KB as PNG at 500px might be only 3 KB as SVG while looking perfectly crisp at any size from 16px to 16000px. For web development, SVG is the definitive format for all icon and logo assets.

Browser Compatibility (2026)

Browser support data as of May 2026, sourced from Can I Use global usage statistics:

• JPEG: 100% — universally supported since the earliest graphical browsers.
• PNG: 100% — universally supported since IE 4 (1997) with full alpha since IE 7.
• GIF: 100% — universally supported including animation.
• SVG: 99%+ — universally supported in all modern browsers. IE 9+ for basic support.
• WebP: 99.4% — supported in Chrome 32+, Firefox 65+, Safari 14+, Edge 18+. The 0.6% without support consists of very old browser versions.
• AVIF: 93% — supported in Chrome 85+, Firefox 93+, Safari 16.4+. Opera and Samsung Internet also support it. The remaining 7% can be handled with a WebP or JPEG fallback using the <picture> element.

Progressive Enhancement Strategy

The recommended approach for production websites is to serve the most efficient format each browser supports. Use the HTML <picture> element to specify AVIF as the first source, WebP as the second, and JPEG as the final fallback. The browser automatically selects the first format it supports. This ensures every visitor gets the smallest possible file while maintaining universal compatibility.

Frequently Asked Questions