rs.Really Simple
Tools

Home / Tools / Image Compressor

Image Compressor

Compress images to make them smaller, or target a specific file size such as 500 KB or 1 MB. Processing happens in your browser.

JPG, PNG or WebP · 10 MB each · 20 images / 100 MB total · up to 50 million pixels

Your images stay in your browser. Originals are never modified.

How it works

  1. Add your images.
  2. Choose automatic compression or a target file size.
  3. Compress and review the result.
  4. Download your smaller images.

A real example

A fictional application form accepts a photo under 500 KB. Add your JPEG, choose Target a specific file size and enter 500 KB. The tool measures actual candidate files, then reports whether the result fits. If necessary, it reduces pixel dimensions and tells you what changed.

For several website photos, use automatic compression. Review individual results, then download them in one ZIP. Already efficient images retain their original bytes instead of being replaced with a larger file.

Automatic compression or a measured target

Automatic mode re-encodes JPEG and WebP at a sensible quality setting, and tries PNG re-encoding without changing format. Pixel dimensions stay unchanged. If the candidate is not smaller, the original is the better result; its bytes and metadata are retained.

Target mode accepts 1 KB to 10 MB, including decimals such as 1.5 MB. Here KB means 1,024 bytes and MB means 1,048,576 bytes. If a website uses decimal units, choose a slightly lower target to leave room.

For JPEG and WebP, the tool tries encoding quality first and searches within a bounded range. If that is not enough, it progressively reduces dimensions proportionally. PNG uses dimension reduction because its encoder has no useful quality slider. Each candidate is encoded and measured; Under target means its actual bytes are at or below your request.

The search is bounded to at most 30 encodes per image and seven dimension levels. It never upscales, and stops before reducing the longest side below 128 pixels. If the target remains out of reach, it offers the smallest measured result with a clear Target not reached message. This is a practical search, not a guarantee of the best possible encoding.

PNG, transparency and visual quality

JPEG stays JPEG, PNG stays PNG and WebP stays WebP. Photographic PNGs can be difficult to shrink without reducing dimensions. This tool never silently converts PNG to JPEG or WebP. PNG and WebP transparency remain supported; the checkerboard preview helps you see transparent areas.

File size measures stored bytes; pixel dimensions measure image width and height. Changing encoding can reduce bytes without changing dimensions. More aggressive targets may need fewer pixels and can reduce visual quality. Use Before and After on a single image to review the result.

Re-encoding may remove metadata or change color rendering. There is no promise of lossless or identical quality, or preservation of EXIF, GPS, color profiles or capture details. When the original is kept, its metadata remains too. Use Photo Metadata Viewer & Remover for a dedicated metadata workflow.

Private batches and practical limits

Image bytes, filenames, previews, dimensions, target sizes and generated files remain in browser memory. They are not uploaded, put in URLs, saved in localStorage or automatically included in feedback. Originals are never modified. Change or remove images to release previews and downloads.

Add up to 20 still JPEG, PNG or WebP images, 10 MB per file and 100 MB total. Images are checked before decoding, with limits of 50 million pixels and 32,768 pixels per side. Batches run sequentially in a worker to limit simultaneous decoding. Available device memory can impose tighter limits.

Each image has its own result or error. Successful results remain downloadable if another file fails; totals cover successful files only. Multiple successful images offer Download All as ZIP, with unique filenames inside. ZIPs have a 100 MB limit; individual downloads remain available if packaging fails.

Animated PNG/WebP, GIF, SVG, HEIC and AVIF are unsupported. A current browser with worker image decoding and encoding is required. There is no server fallback or format conversion.

Frequently asked questions

Are my images uploaded?

No. Validation, decoding, compression, previews and ZIP creation happen locally in your browser. Normal site requests load RST, but image data and settings are not uploaded or automatically attached to feedback.

How do I compress an image to 500 KB?

Choose Target a specific file size and enter 500 with KB selected, or use the 500 KB preset. Compress and check Under target. The tool measures actual encoded bytes and reports honestly if the target is missed.

Can I compress an image to 1 MB?

Yes. Choose MB and enter 1, or use its preset. Decimal targets such as 1.5 MB also work. The accepted range is 1 KB to 10 MB.

Will compression change the image dimensions?

Automatic mode keeps dimensions. Target mode may reduce them proportionally after trying encoding quality where effective. Original and result dimensions are shown, with a visible notice when changed.

Does image compression reduce quality?

It can. JPEG and WebP re-encoding and smaller dimensions can lose detail. Aggressive targets may noticeably affect appearance. Review the preview; there is no guarantee of identical or lossless quality.

Why can't some PNG files get much smaller?

PNG is often already efficiently encoded, and its browser encoder does not offer JPEG-style quality control. Automatic mode may keep the original. Target mode can reduce dimensions, but never silently converts format or removes transparency.

Can I compress several images at once?

Yes. Add up to 20 images within the file and batch limits. Each is processed independently and sequentially. Download individual results or all successful images in one ZIP. Failed files are identified separately.

Does compression remove photo metadata?

Re-encoded outputs may not retain all metadata. This is not a verified metadata-removal tool. If the original is kept because it is smaller or already meets the target, its original bytes and metadata remain.

Does this change my original image?

No. Downloads are new files. If the original is the better result, the download is a copy of its bytes. Keep your originals as backups.

Can I use this on my phone?

Yes, with a current browser supporting local worker image decoding and encoding. Use the native file picker and touch controls. Large images can exceed available device memory; try smaller files or a smaller batch.

Related tools

Missing something?