How many images can I process?

Browser processing handles dozens to hundreds of images. For thousands, consider desktop tools for better performance.

Is my image processed on a server?

Processing happens locally in your browser. Your images are never uploaded to any server, ensuring complete privacy.

Bulk Image Compressor

Convert and optimize images for different uses with this bulk image compressor. Transform images between formats while maintaining quality.

When to Use This Tool

Compressing many images at once for batch optimization.

Key Benefits

Save hours of work
Consistent settings
Process entire folders
Maintain organization

Pro Tip

Test settings on a few images first before processing large batches.

Supported Formats

Format	Best For	Supports
JPEG	Photos	Lossy compression
PNG	Graphics, screenshots	Transparency, lossless
WebP	Web images	Both lossy and transparency
GIF	Animations	Limited colors

Optimization Tips

1. Use JPEG for photos to reduce file size 2. Choose PNG when you need transparency 3. Consider WebP for modern browsers 4. Compress images before uploading to websites

Compressing a Whole Folder

Batch processing runs the same settings across every file, which is right for a consistent set and wrong for a mixed one — a screenshot and a photograph want different formats and different quality.

Source type	Format	Quality
Photographs	WebP or JPG	75–85
Screenshots, UI	WebP or PNG	85–95
Logos, line art	SVG, else PNG	lossless
Illustrations with flat colour	PNG or lossless WebP	lossless

Sort by type first, then batch each group.

Everything here runs in your browser, so the practical limits are memory and time rather than an upload cap: a few dozen images at a time is comfortable, several hundred large ones will make the tab struggle. There is no file to upload and nothing leaves the machine.

Sizing Before Compressing

Resizing beats compressing. Halving an image's dimensions removes 75% of its pixels, which no quality setting can match, and a 4000px photo displayed at 800px is wasting 96% of what it downloads.

Displayed at	Serve (1×)	Serve (2× for retina)
400px	400px	800px
800px	800px	1600px
1200px	1200px	2400px

Above 2× there is no visible benefit on any current display, and the file size keeps rising.

Quality Settings That Hold Up

Setting	Looks	Use for
95–100	Indistinguishable, large	Masters and print
80–90	Very good	Hero images, product photography
70–80	Good	Most web content
50–70	Visible artefacts on detail	Thumbnails
Below 50	Obvious	Nothing

Around 75–85 is where the curve bends: below it quality falls quickly, above it file size rises quickly for no visible gain.

Everything Runs Locally

Conversion and compression here use a canvas in your own tab. No file is uploaded, nothing is stored, and the work continues offline once the page has loaded. That is worth knowing for anything containing faces, documents or unreleased work — most online image tools upload by necessity, because they process server-side.

Getting the Rest of the Win

Serve modern formats with a fallback. with AVIF, then WebP, then JPG.
Always set width and height. Without them the page reflows on load, which

Google measures as Cumulative Layout Shift.

Lazy-load below the fold — and never the hero, since loading="lazy" on it delays

the exact element Largest Contentful Paint measures.

Strip metadata. EXIF can carry GPS coordinates and adds weight to every copy.

Bulk Image Compressor