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Image Compressor

Free online batch image compressor for JPG, PNG, WebP. Runs locally in your browser, no upload, private and secure, no software to install

Drag images here or click to upload

JPG, PNG, WebP supported. Select multiple at once, up to 50MB each

Batch compression: pick many images, set once, process all in one click

All processing happens locally in your browser — images are never uploaded to any server

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Compress images in three steps

No software to install — just open the page, everything runs locally

1

Add your images

Drop images into the upload area, or click "Select Images" to pick several at once. JPG, PNG, and WebP are all supported.

Tip: you can select multiple images for batch compression

2

Set options

Pick a quality preset and output format, and add a target width if you want to resize.

Balanced preset gives the best size-to-quality ratio

3

Compress and download

Hit "Compress All", then grab each file or the whole batch as a ZIP.

Converting to WebP typically saves another 30%-70%

JPG vs PNG vs WebP

Understand the core differences between the three major image formats and pick the best one for your scenario

JPG

  • Lossy compression, small file size
  • Great for photos and gradients
  • Universally compatible across all platforms
  • No transparency support
  • Quality degrades with repeated compression

PNG

  • Lossless compression, perfect quality
  • Supports transparent backgrounds
  • Ideal for icons, line art, and screenshots
  • File size is usually larger
  • Limited compression ratio

WEBP

  • 30%-70% smaller than JPG/PNG at same quality
  • Supports both lossy and lossless modes
  • Supports transparency and animation
  • Supported by all modern browsers
  • Very old browsers don't support it

JPG vs PNG vs WebP — Key Parameters

FeatureJPGPNGWebP
CompressionLossyLosslessLossy/Lossless
TransparencyNoYesYes
AnimationNoNoYes
Typical ratioHighLowVery high
Browser supportAllAllModern browsers
Best forPhotosIcons/ScreenshotsGeneral choice
Size (same quality)MediumLargeSmallest

Why compress images locally

Understand the core advantages of compressing images right in your browser

Privacy & Security

Fully local

All compression happens in the browser — your images never leave the device

No data residue

Memory is released on page close, no file copies are ever stored

No account needed

No sign-up or login required; open and use, zero data collection

Professional Compression

Canvas API

Built on the browser's native Canvas interface — fast and reliable

Multi-format

Read and write JPG, PNG, and WebP, switch freely between them

Smart fallback

If compression would make the file larger, the original is kept

Efficient & Convenient

No software to install

Open your browser and start — cross-platform with zero barrier

Batch in one click

Pick dozens of images, set options once, compress them all together

Completely free

No feature limits, no usage caps, no watermarks

How image compression works

Understand the core technical pipeline of browser-based image compression

Implementation pipeline

1

File reading

The FileReader API reads the image as a DataURL and creates an in-memory Image object

2

Resize

If a target width is set, the canvas dimensions are calculated proportionally

3

Canvas drawing

The image is drawn onto a Canvas — PNG as-is, JPG/WebP with a white background fill

4

Quality compression

canvas.toBlob() is called with the configured quality for lossy or lossless compression

5

Smart comparison

The compressed size is compared to the original; if larger, the original is kept (except PNG)

6

Export

A compressed Blob is generated for individual download or zipped into a batch

Core features of the image compressor

Professional-grade image compression and format conversion

Processed locally

Images are compressed in the browser and never leave your device, so your files stay private

Completely free

No limits on count, size, or watermarks, and no sign-up required. Free to use, no catch

Batch in one click

Pick dozens of images at once, set options once, then compress and download them as a ZIP

Convert between formats

Read and write JPG, PNG, and WebP, so you can switch to the smaller WebP on the way out

Common use cases for image compression

Smaller images come in handy more often than you'd think

Website and blog images

Smaller files load faster and use less bandwidth, which also helps your search ranking

Chat and social sharing

Messaging apps and feeds dislike large files, so shrink them first for smoother sending

E-commerce product shots

Marketplaces cap upload sizes; batch-slim them before listing to save time

ID and personal photos

Email attachments and forms often cap file size, so compression gets them under the limit

Email attachments

Compressed attachments are smaller, send more smoothly, and download faster for recipients

Mobile sharing

Phone photos are often too large; compress before sharing to save time and data

Which format should you pick

Match the format to the job and you get both size and quality

JPG

Best for photos and smooth gradients

Lossy and small, but no transparency support.

PNG

Use it when you need transparency or crisp lines

Lossless and faithful, but usually larger.

WebP

Pick it when you want the smallest file

Balances quality and size, supported by all modern browsers.

How the compression works

Built on native browser APIs — no network needed

Lossy compression: JPG and WebP drop redundant detail you barely notice, shrinking the file a lot.

Lossless keep: choosing PNG keeps every pixel, good for transparency and line art, but savings are limited.

Switch to WebP: at the same quality, WebP is usually 30%–70% smaller than JPG/PNG, making it the top pick for size.

Smart fallback: if a file would grow after compressing (say an already-tiny PNG), the original is kept as-is.

Image compression FAQ

Answers to common questions about compression, formats, and usage

Is this image compressor really free? Any limit?

Can I compress images in batch? How?

Are my images uploaded to a server during compression?

Which image formats are supported?

Will quality drop after compression?

Does it work on mobile?

How much can it shrink an image?

Why does the file sometimes get larger after compression?

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