JPG vs PNG vs WebP: la comparación definitiva de formatos de imagen — WebConverter

Choosing the right image format can feel like a minor decision, but it has an outsized impact on page load speed, visual quality, bandwidth costs, and even SEO rankings. The three formats that dominate the web — JPEG (often written JPG), PNG, and WebP — each have distinct strengths and trade-offs.

This guide provides a thorough, side-by-side comparison so you can make the right choice every time. We cover compression mechanics, quality differences, browser support, performance benchmarks, and clear recommendations for every common scenario. If you have already read our PNG vs JPEG deep dive, this guide expands the comparison to include WebP and offers updated benchmark data.

Quick Comparison Table

JPEG / JPG: The Photography Standard

JPEG (Joint Photographic Experts Group) has been the web's default photograph format for over 30 years. It uses lossy compression based on the Discrete Cosine Transform (DCT), which divides the image into 8×8 pixel blocks and removes high-frequency detail that the human eye is least likely to notice.

Strengths

• Excellent compression for photos. A quality setting of 80 typically reduces a photograph to 5–10% of its uncompressed size with minimal visible degradation.
• Universal compatibility. Every browser, email client, operating system, and image editor supports JPEG. It is the safest choice when you have zero control over the viewer's software.
• Small file sizes. For photographic content, JPEG consistently produces smaller files than PNG.
• Progressive loading. Progressive JPEGs render a low-quality preview first, then sharpen as data arrives — a nice UX improvement for slow connections.

Weaknesses

• No transparency. JPEG does not support alpha channels. If you need a transparent background, JPEG is off the table.
• Generation loss. Each time a JPEG is opened, edited, and re-saved, it is re-compressed and loses more quality. After several rounds of re-compression, artefacts become clearly visible.
• Poor with sharp edges and text. The block-based compression creates visible "ringing" artefacts around sharp contrasts — thin lines, text, and UI elements suffer.
• No animation. JPEG is a single-frame format.

Convert to JPEG: Use the Image to JPEG converter for fast, private conversion in your browser.

PNG: Lossless Quality with Transparency

PNG (Portable Network Graphics) was designed as a patent-free replacement for GIF. It uses lossless compression — the decompressed image is identical to the original, pixel for pixel.

Strengths

• Perfect quality. No data is discarded. What you see is exactly what was saved.
• Full alpha transparency. PNG supports an 8-bit alpha channel, enabling smooth, anti-aliased transparency — not just the binary on/off transparency of GIF.
• Ideal for graphics. Screenshots, diagrams, logos, text-heavy images, and UI elements look crisp because there are no compression artefacts.
• No generation loss. You can open, edit, and re-save a PNG indefinitely without quality degradation.
• Universal support. Like JPEG, PNG is supported everywhere.

Weaknesses

• Large files for photos. Lossless compression is inherently less efficient for complex photographic content. A photo saved as PNG is typically 5–10× larger than the equivalent JPEG.
• No native animation. APNG exists but has limited support and tooling compared to WebP animation or GIF.
• Overkill for simple use cases. If pixel-perfect quality is not needed, PNG wastes bandwidth.

Convert to PNG: Use the Image to PNG converter for lossless conversion with full transparency support.

WebP: The Modern All-Rounder

WebP is an image format developed by Google and released in 2010. It supports both lossy and lossless compression, transparency, and even animation — effectively combining the best features of JPEG, PNG, and GIF into a single format.

Strengths

• Superior compression. Lossy WebP is 25–35% smaller than JPEG at equivalent visual quality (per Google's own studies and independent benchmarks). Lossless WebP is 26% smaller than PNG on average.
• Transparency support. Lossy WebP with alpha is a game-changer — it gives you transparency at a fraction of PNG's file size. A product photo on a transparent background, for example, might be 200 KB as PNG but 50 KB as lossy WebP.
• Animation. Animated WebP replaces GIF with dramatically smaller files and better colour depth (24-bit vs GIF's 8-bit).
• Versatile. One format handles photos, graphics, transparency, and animation. This simplifies your asset pipeline.

Weaknesses

• Not quite universal. While WebP is supported by all major browsers (Chrome, Firefox, Safari 14+, Edge), some older software, email clients, and native image viewers still do not support it.
• Maximum dimensions. WebP images are limited to 16,383 × 16,383 pixels. This is rarely an issue for web use but can matter for print or scientific imaging.
• Editing support. Some older versions of Photoshop and other design tools require plugins to open WebP files, though support is improving rapidly.

Convert to WebP: Use the Image to WebP converter for the best file-size-to-quality ratio on the web.

File Size Comparison: Real-World Benchmarks

Numbers tell the story better than adjectives. Here are typical file sizes for a 1920 × 1080 photograph and a 1200 × 800 screenshot, converted to each format:

Photograph (1920 × 1080, complex scene)

Screenshot (1200 × 800, UI with text)

The pattern is clear: WebP wins on file size in every category. For photos, lossy WebP is about 30% smaller than JPEG. For graphics, lossless WebP is about 30–40% smaller than PNG.

Quality Differences: What You Can Actually See

File size means nothing if the image looks bad. Here is what to expect visually:

• JPEG at quality 80–90: Virtually indistinguishable from the original for photographs. Close inspection may reveal slight softening in fine texture. Artefacts become noticeable around sharp text or thin lines.
• PNG: Pixel-perfect. No quality difference whatsoever — it is an exact copy of the original.
• WebP at quality 80: Visually equivalent to JPEG at quality 85–90, but at a smaller file size. WebP's algorithm handles gradients and fine detail slightly better than JPEG, producing fewer block artefacts.
• WebP lossless: Pixel-perfect, identical to PNG, but smaller.

The bottom line: at equivalent file sizes, WebP looks better than JPEG. At equivalent quality, WebP is smaller. PNG and lossless WebP both look perfect.

Browser Support in 2025

WebP's remaining 3% gap consists primarily of users on old, unupdated devices. For most websites, this is an acceptable trade-off. If you need absolute universal compatibility, serve JPEG/PNG as a fallback using the HTML <picture> element:

<picture>
  <source srcset="image.webp" type="image/webp">
  <img src="image.jpg" alt="Description">
</picture>

When to Use Each Format

Use JPEG When:

• You are sending images via email (not all clients support WebP)
• You need compatibility with legacy systems (old CMS, outdated browsers)
• The recipient needs to open the file in older desktop software
• You are uploading to platforms that re-compress to JPEG anyway (many social networks)

Use PNG When:

• You need pixel-perfect lossless quality (screenshots, technical diagrams)
• The image contains text, sharp lines, or flat colours that show JPEG artefacts
• You need transparency and are targeting platforms that do not support WebP
• You are creating assets for print or archival purposes

Use WebP When:

• You are optimising images for a website or web application
• You want the smallest possible file size without visible quality loss
• You need transparency with small file sizes (product images on transparent backgrounds)
• You are building a performance-focused site and care about Core Web Vitals
• You want one format that handles both photos and graphics well

Converting Between Formats

WebConverter makes it easy to switch between JPEG, PNG, and WebP — entirely in your browser, with no file uploads. Your images stay on your device.

• Convert any image to JPEG
• Convert any image to PNG
• Convert any image to WebP
• General image converter — supports all formats

Frequently Asked Questions

Is WebP better than JPEG?

For web use, yes. WebP produces files 25–35% smaller than JPEG at the same visual quality, supports transparency, and handles both photographic and graphic content well. The only scenario where JPEG is still preferable is when you need universal compatibility with legacy software or email clients.

Is PNG better than JPEG?

It depends on the image. PNG is better for screenshots, graphics, logos, and anything with sharp edges or text — it preserves every pixel perfectly. But PNG files are much larger than JPEG for photographs. Use PNG when quality and accuracy matter more than file size. For a detailed comparison, see our PNG vs JPEG article.

Does WebP support transparency?

Yes. Both lossy and lossless WebP support an 8-bit alpha channel for transparency. This is one of WebP's biggest advantages — you can have transparent images at much smaller file sizes than PNG.

Can I convert WebP back to JPEG or PNG?

Yes. You can convert WebP to JPEG or PNG using WebConverter. However, if the original WebP used lossy compression, converting to PNG will not recover the lost quality — the image will simply be a lossless copy of the already-compressed version.

Which format is best for SEO?

Google recommends next-gen formats like WebP. Smaller images improve page load speed, which is a direct ranking factor. Google's PageSpeed Insights tool specifically flags images that could benefit from WebP conversion. Using WebP can positively impact your Core Web Vitals scores.

Will WebP replace JPEG and PNG?

WebP is well on its way to becoming the default web image format, but JPEG and PNG will persist for years in email, print workflows, and legacy systems. For new web projects, WebP is the best default choice.