Compress hundreds of images in bulk directly in your browser. Optimize quality, target max file sizes, and download separately or batch download in a ZIP file—completely private and zero upload waiting time.
Click to select images or drag and drop here
Supports JPG, PNG, WebP, BMP. Batch upload 100+ files
Lower quality value = smaller file size with visible compression; Higher value = better clarity with larger size. If the compressed result exceeds “Max Size (KB)”, the tool will automatically step down the quality to comply with the threshold.
Fast, local, and privacy-oriented batch image optimization without server bottlenecks.
All compression and ZIP packaging run directly in your browser memory. Your sensitive images never leave your computer or touch any cloud server.
Save compressed images individually as soon as they are ready, or export all files at once in a single ZIP archive with automatic duplicate renaming.
Customize your compression ratio with an interactive slider, or define a target maximum KB limit so your compressed photos meet website upload rules.
When you drop images into the tool, your browser reads them locally via the File API. Each image is then rendered on an off-screen HTML5 Canvas and re-encoded using high-efficiency JPEG compression algorithms. There are zero remote network requests—you can inspect your browser's Network tab to confirm that no image payloads are ever uploaded.
To ensure smooth processing when compressing 100+ high-resolution photos, our engine uses an asynchronous sequential queue: images are handled one by one, immediately releasing canvas memory after completion. Once all items are processed, an in-browser ZIP generator packs them directly inside your computer's RAM.
Note: JPEG uses lossy compression and does not support alpha channels. Transparent areas in PNG files will be rendered on a solid white background upon export. If transparency is essential, please preserve your original PNG assets.
Everything you need to know about bulk image compression, privacy, and file limits.
No. All file reading, resizing, compression, and ZIP archiving take place entirely within your local browser JavaScript engine. You can even disconnect your internet connection after loading the page and it will continue to function seamlessly.
There is no hardcoded limitation. Because the tool runs a one-by-one memory cleanup queue, processing 100 to 200+ images is usually fast and stable on modern devices.
Standard JPEG encoding provides the highest universal compression ratio across all devices. However, JPEG does not support transparency, so transparent pixels are automatically filled with white.
The compressor first evaluates your chosen Quality slider. If the resulting file exceeds your "Max Size (KB)" limit, the tool automatically recalculates and compresses further until it fits under your cap.
The ZIP builder automatically detects duplicate names and appends sequential numbering (such as photo (1).jpg) so that no images overwrite each other.