Zro7To compress an image without visible quality loss, use Zro7 Compress Image: pick AVIF at quality 60, WebP at quality 75, or MozJPEG at quality 80. All three typically shrink a photo 40–70% while staying visually identical to the original. Everything runs in your browser via the same Squoosh codecs Google publishes.
Which codec should you actually use?
- AVIF — smallest files, best quality-per-byte in 2026. Universal browser support. Slower to encode. Use when file size matters most.
- WebP — 25–35% smaller than JPEG at matching quality, fast to encode, universally supported. Great default for the web.
- MozJPEG — a smarter JPEG encoder. Use when you need JPEG for compatibility (email attachments, older CMSes, print pipelines) but want it small.
Quality settings that look identical
For photographic content, humans stop noticing artifacts above roughly: MozJPEG 80, WebP 75, AVIF 60. Below those, banding and blocky skies appear. For screenshots and diagrams, prefer PNG or WebP-lossless — JPEG family codecs blur crisp edges.
Steps
- Open Compress Image.
- Drop one image or a batch.
- Choose codec (AVIF / WebP / MozJPEG) and quality.
- Preview the before/after size and download.
Why this is faster than TinyPNG
TinyPNG uploads, encodes on their servers, then downloads. On a slow connection that's 3–4 seconds of round-trip per image. Zro7 skips the round trip entirely — a 5 MB photo re-encoded to AVIF locally is done in under a second on a modern laptop, and 20 photos in parallel don't touch anyone's bandwidth quota.