Compress Image — Reduce JPEG, PNG, WebP & AVIF File Size in Your Browser
Updated June 2026 · Covers compress image, reduce image size, image compressor, batch and folder mode
Photos out of a modern phone are 3–5 MB each. A folder of 200 of them is a gigabyte. Upload portals choke; email bounces; cloud storage fills up. This guide walks through how to compress images on your own machine — JPEG, PNG, WebP, AVIF, and HEIC — with no upload, no signup, and no 20-file batch caps. The technical sections also cover which format gives the smallest file at the same visual quality, because the format choice usually matters more than the quality slider.
How to compress an image
- Open Squeeze. Visit essexsoftware.com/squeeze. Loads in any modern browser; no signup.
- Drop your image. Drag one image or an entire folder into the dropzone. Squeeze accepts JPG, PNG, WebP, AVIF, and HEIC.
- Pick output format and quality. Keep the original format and just re-encode at a smaller quality, or convert to a more efficient format (WebP, AVIF). Quality sliders are per-format — JPEG, WebP, and AVIF each have their own.
- Download the result. A single image downloads as a single file. A folder downloads as a ZIP that preserves the original structure. Your originals are untouched.
Open Squeeze
Compress images in your browser. Free, no signup, no upload, no batch cap.
Which format gives the smallest file?
The single biggest lever for image file size isn't the quality slider — it's the format. Modern formats (AVIF, WebP) compress 30–80% smaller than JPEG at the same visual quality. A 4 MB JPEG photo often becomes a 600 KB WebP or 400 KB AVIF with no visible difference.
AVIF
Best for photos
Smallest file size. Roughly 50% smaller than JPEG at the same quality. Supported in Chrome, Edge, Firefox, and Safari 16+. Encoding is slow; decoding is fast. Use when output is going on a modern website.
WebP
Best universal modern
30% smaller than JPEG. Supported everywhere since 2020 (including Safari, iOS, Android). Encoding is fast. Use when you want modern compression without the AVIF support concerns.
JPEG
Best for compatibility
Universal — every device, every app, every web form. Larger files than AVIF/WebP at the same quality, but no support questions. Use when output goes to "I don't know who will open this".
PNG (re-optimized)
Best for graphics
Lossless. Required for transparent backgrounds. Squeeze runs oxipng in your browser to shrink existing PNGs 10–40% with no quality change. Use for logos, screenshots, and UI graphics.
Quick rule of thumb:
- Photos for a modern website → AVIF (or WebP as fallback).
- Photos for email, document attachment, "I don't know" → JPEG at quality 80.
- Logos, icons, UI screenshots, anything with sharp edges or transparency → PNG (Squeeze runs oxipng over it).
- iPhone HEIC photos to email or upload → JPEG at quality 80. (Most non-Apple platforms still struggle with HEIC.)
Quality presets that don't visibly hurt
Every lossy format trades quality for size on a sliding scale. Past a certain point you save bytes you can see in the output. The thresholds below are conservative starting points — what looks identical to most viewers on most images:
| Format | Visually lossless quality | Typical size reduction vs original |
|---|---|---|
| JPEG | q80–85 | 40–60% smaller |
| WebP | q75–80 | 60–75% smaller |
| AVIF | q50–60 | 70–85% smaller |
| PNG (lossless re-opt) | n/a — lossless | 10–40% smaller |
If output looks fine at the recommended quality, push the slider lower and re-check. The point of diminishing returns differs by image — busy photos hide compression better than gradients and flat colour.
Compress a whole folder at once
Most online image compressors cap their free tier at 20 images per batch. Squeeze has no cap — drop a folder of 500 photos and it processes them in your browser, then delivers a ZIP. The cost to us is zero because we're not running CPU on a server.
Common batch use cases:
- Trip photo backup. A folder of 800 phone photos becomes a few hundred MB instead of 3 GB.
- E-commerce product catalogue. Convert 200 product JPGs to WebP for the web in one pass.
- Email a folder of scans. Compress everything down before zipping for an attachment.
- iPhone HEIC → JPEG. Convert a year of HEIC backup into JPGs your non-Apple app can read.
How we compare to TinyPNG, ILoveIMG, Compressor.io
| Tool | Free batch limit | Watermark | File leaves your device? | Format choice on free |
|---|---|---|---|---|
| Essex Squeeze (this site) | Unlimited | No | No — runs in your browser | JPEG, PNG, WebP, AVIF |
| TinyPNG / TinyJPG | 20 files / batch | No | Yes — uploaded | Input format only |
| ILoveIMG | Login for batch > a few | No | Yes — uploaded | Multiple formats |
| Compressor.io | 1 file / page reload (free) | No | Yes — uploaded | JPEG, PNG, WebP |
| Squoosh (Google) | 1 at a time | No | No — runs in browser | JPEG, PNG, WebP, AVIF, more |
Squoosh is the closest peer technically — it also runs in the browser. We differ on batch: Squoosh processes one image at a time, which becomes a wrist injury at 200 photos. Squeeze processes folders.
TinyPNG, ILoveIMG, and Compressor.io upload your files. Fine for non-sensitive content; not fine for medical scans, IDs, or anything containing personal photos you wouldn't want passing through a stranger's server.
Try it now
Compress images in your browser — no signup, no caps
Drop one image or a folder of 500. Convert formats. No upload, no watermark, no daily limit.
FAQ
How do I compress an image without losing quality?
True lossless compression for JPEG, WebP, and AVIF is limited — these formats trade quality for size by design. The practical approach is visually lossless compression: pick a quality preset (75–85 for JPEG, 70–80 for WebP, 50–60 for AVIF) that drops file size 40–70% with no visible difference. PNG can be losslessly recompressed with oxipng, which Squeeze runs in your browser — same pixels, smaller file.
What's the best image format for smaller file size?
For photographs: AVIF gives the smallest files at the same visual quality, followed by WebP, then JPEG. AVIF is supported in Chrome, Edge, Firefox, and Safari 16+. For logos, screenshots, and graphics with sharp edges: WebP lossless or PNG (re-optimized with oxipng) is usually best — JPEG and AVIF lossy modes introduce blur on solid colour boundaries.
Can I compress multiple images at once?
Yes. Drop a folder of any number of images and Squeeze processes them in your browser. The output is delivered as a ZIP preserving the folder structure. Most online image compressors cap their free tier at 20 images at a time — Squeeze has no cap because we don't pay per-image on a server.
Do you upload my images to a server?
No. All compression and format conversion runs in your browser via WebAssembly. The image data never leaves your device. You can verify by disconnecting from Wi-Fi after the page loads — Squeeze keeps working.
How do I convert PNG to WebP or AVIF?
Drop the PNG into Squeeze, change the Output Format dropdown to WebP or AVIF, and download. Both formats deliver smaller file size than PNG at similar visual quality. AVIF gives the smallest output; WebP has slightly better browser support.
Can I convert HEIC photos from my iPhone?
Yes. iPhone photos (HEIC/HEIF) are accepted as input. The default output is JPEG, which works in every app and every web upload form. You can also convert HEIC to WebP or AVIF if you're staying in modern browsers.
Will compressed images lose EXIF data?
Squeeze preserves the relevant orientation metadata so images don't end up rotated incorrectly. Other EXIF data (camera model, GPS location, timestamp) is stripped by default — for most use cases this is what you want, especially for photos you'll share publicly.