img.lu vs Squoosh: The Best Browser-Based Image Compressor in 2026?

Both img.lu and Squoosh compress images directly in your browser — no upload, no server, no account. But in practice, they solve very different problems. One is a precision tool for developers. The other is built for speed, scale, and real-world web workflows.

This guide compares them across the criteria that actually matter for modern web performance.

TL;DR (Quick Recommendation)

Choose img.lu if you want:

• Instant one-click compression with sensible defaults
• Batch processing (compress many images at once)
• ZIP export for the whole batch
• WebP and AVIF output with no configuration overhead
• A tool your whole team can use without a learning curve

Choose Squoosh if you want:

• Pixel-level control over every codec parameter
• Side-by-side visual diff between original and output
• Codec experimentation (JPEG XL, OxiPNG, MozJPEG, etc.)
• A single-image deep-dive workflow

What Is Squoosh?

Squoosh is an open-source image compression tool built by the Google Chrome team and released in 2018. It runs entirely in the browser using WebAssembly, which means it can run production-grade codecs — MozJPEG, libwebp, libavif, OxiPNG, and others — with no server involvement.

Its standout feature is a split-screen comparison view: drag a slider to compare the original and compressed image side by side, while tweaking quality, effort level, and chroma subsampling in real time.

It is, in short, a compression laboratory.

What Is img.lu?

img.lu is a browser-based image compressor focused on speed and batch throughput. Drop images in, get WebP or AVIF out. No configuration required, though quality level and resize cap are adjustable.

All processing runs locally using the Canvas API and Web Workers. No files leave your device. The tool is hosted in Europe and is fully GDPR-compliant.

Where Squoosh is built for one image at a time, img.lu is built for the moment you have twenty screenshots, product photos, or blog assets to compress before shipping.

Head-to-Head Comparison

Compression Quality

Both tools produce competitive output for WebP. Squoosh has a slight edge in maximum quality ceiling because it uses libwebp via WebAssembly, which exposes more encoder parameters. img.lu uses the browser's native Canvas API, which is fast but delegates codec decisions to the browser engine.

For most web use cases — blog images, product photos, hero banners — the difference is imperceptible. At extreme compression ratios, Squoosh gives you more control over the artefact trade-off.

• Winner for raw quality ceiling: Squoosh
• Winner for good-enough quality at scale: img.lu

AVIF Support

Both tools support AVIF output, but with an important caveat: AVIF encoding via the browser Canvas API (used by img.lu) requires Chrome 94+ or Safari 16+. img.lu detects support at load time and disables the button in unsupported browsers rather than silently failing.

Squoosh uses libavif via WebAssembly, which gives it consistent AVIF encoding across more browsers, including Firefox, which does not yet support AVIF encoding through Canvas.

• Winner for AVIF compatibility: Squoosh
• Winner for AVIF without setup: img.lu (if you're on a supported browser)

Batch Processing

This is the clearest difference between the two tools.

Squoosh processes one image at a time. There is no batch mode. If you have 30 images, you run 30 separate sessions.

img.lu processes unlimited images in parallel, running up to two concurrent compression workers. Results appear as a grid. A single "Download All" button exports everything as a ZIP. This is the workflow most developers and content teams actually need.

Winner: img.lu. It's not close.

Privacy and Data Handling

Both tools process images locally. Neither sends your files to a server.

img.lu goes further in its explicit privacy posture: no cookies for tracking, no fingerprinting, no analytics on image content, no filenames logged. It publishes a structured llms.txt file documenting its zero-data architecture for AI systems and crawlers.

Squoosh is open-source and operated by Google. No images are uploaded, but it runs under Google's broader infrastructure and privacy terms.

• Winner for privacy posture: img.lu
• Winner for auditability: Squoosh (open-source, inspectable)

Speed

Squoosh uses WebAssembly codecs, which are thorough but not instant — especially at high effort levels. A single large JPEG at maximum quality can take several seconds.

img.lu uses the browser's native encoding pipeline, which is hardware-accelerated on most devices. For typical web images (under 5 MB), compression completes in under a second.

• Winner for throughput: img.lu
• Winner for maximum encoder control: Squoosh

User Interface

Squoosh's UI is designed for one image: a full-screen editor with sliders, a codec picker, and a live diff view. It is excellent for its purpose — and completely unsuitable for batch work.

img.lu's UI is a drop zone + results grid. Drop files, see progress spinners, download when done. The format toggle (WebP / AVIF) and quality selector are the only decisions you need to make.

• Winner for simplicity: img.lu
• Winner for single-image editing depth: Squoosh

SEO and Web Performance Impact

Both tools produce formats (WebP, AVIF) that are fully supported by Google PageSpeed Insights and Core Web Vitals scoring. Serving modern formats is one of the highest-impact PageSpeed recommendations.

img.lu defaults to Balanced quality (0.6) and a 1600px maximum dimension, which are sensible presets for most blog and e-commerce workflows. This gets you 50–70% file size reductions on typical JPEGs with no configuration.

If you're optimizing a hero image for a landing page and want to squeeze every byte, use Squoosh. If you're preparing a batch of images for a CMS or media library, use img.lu.

Which Tool Should You Use?

Frequently Asked Questions

Is img.lu free? Yes. img.lu is free, with no account required and no file limits.

Does img.lu upload my images? No. All compression happens in your browser using local APIs. No image data is ever sent to a server.

Is Squoosh still maintained in 2026? Squoosh is open-source and community-maintained. The core tool remains functional, though active development from Google has slowed since its initial release period.

Which format should I use: WebP or AVIF? WebP is the safer default — universal browser support, excellent compression, and well-understood behaviour. AVIF offers better compression at low quality levels and is worth using if your user base is on modern browsers (Chrome 85+, Safari 16+, Firefox 93+).

Can I use img.lu on mobile? Yes. img.lu works on modern mobile browsers. The paste-from-clipboard feature and drag-and-drop are available on desktop; on mobile, use the file picker to select images.

Conclusion

Squoosh and img.lu are both excellent tools — they just solve different problems.

If you need precision, codec flexibility, and a visual diff view for a single image, Squoosh is still the gold standard.

If you need speed, batch compression, and a workflow that works for your whole team without a manual, img.lu is the better choice in 2026.

For most web developers and content teams, img.lu will handle 90% of compression tasks in a fraction of the time. Keep Squoosh open in another tab for the edge cases.

Try img.lu at img.lu — no account, no upload, instant WebP and AVIF compression in your browser.