Is this image compressor free?

Yes — no registration, no usage limits and no watermarks. It runs entirely in your browser and continues to work offline once the page has loaded.

What quality should I use to compress images for the web?

For most web images 75–80% is a good balance, typically cutting file size substantially while remaining visually indistinguishable at screen resolution. Use 85–90% for hero images and product photography, and 60–70% for thumbnails.

Compress Image Online Free

Drag and drop JPG, PNG or WebP files to reduce image file size in your browser. The tool tries several encodings and keeps the smallest — and never returns a file bigger than the one you started with. No uploads, no account, works offline.
Compress JPG PNG WebP · Batch Compress · 100% Private

Drag & Drop Images Here

Supports JPG, PNG and WebP — compress multiple images at once

Compression Settings

Quality 80% Good balance of size and quality — recommended for web images.

Output Auto compares JPG, WebP and PNG and keeps whichever is smallest. Transparency is preserved automatically.

How It Works

1. Drop or Select Images

Drag JPG, PNG or WebP files into the zone above, or click to browse. Select several to compress multiple images at once.

2. Set Quality & Compress

Pick a quality level (80% suits most web images) and click Compress Images. Everything runs locally in your browser.

3. Download the Results

Each result shows before and after sizes plus the saving. Download files individually or use Download All.

What Is an Online Image Compressor?

An online image compressor reduces the file size of images such as JPG, PNG and WebP while preserving as much visual quality as possible. Compression works either by removing data that can be reconstructed exactly (lossless) or by discarding detail the eye is unlikely to notice in exchange for a much smaller file (lossy).

This free online image compressor decodes your image with the browser's Canvas API and re-encodes it at your chosen quality, entirely on your own device. Nothing is uploaded, so it is also the most private way to reduce image file size.

Lossless vs Lossy Compression

Type	How it works	Best for	Typical saving
Lossless (PNG, WebP lossless)	Reorganises data — every pixel is reconstructed exactly	Logos, screenshots, line art	10–30%
Lossy, quality 80–90%	Discards detail that is hard to perceive	Photos for the web	40–70%
Lossy, quality 60–75%	Visible only on close inspection	Thumbnails, email attachments	70–85%

Why a PNG can get bigger, and how this tool avoids it

A well-made PNG is often already optimised — an indexed palette, a reduced bit depth, no metadata. When a browser draws that image to a canvas and saves it again, all of that is lost: the canvas always produces a full 32-bit RGBA PNG, which can be several times the size of the original. The PNG format also has no quality setting, so a quality slider has no effect on it whatsoever.

This tool handles that in two ways. To actually shrink a PNG, it converts to WebP or JPEG, formats that do respond to quality — choosing WebP when the image has transparency so the alpha channel survives. And before showing you any result, it compares every candidate against your original file: if nothing is smaller, the original is kept and reported as already optimised. The download is never larger than the file you started with.

Recommended Quality Settings

Web pages and faster loading: 75–80% — usually cuts size by half or more with no visible difference at screen resolution.
Social media: 80–85% — platforms re-compress on upload, so starting higher gives a better final result.
Email attachments: 65–75% — small enough for most attachment limits.
Archive or print source: 90–95% — near-lossless, keeps maximum detail.
Thumbnails and previews: 60–70% — displayed small enough that the loss is invisible.

Why Compress Images for Faster Loading

Images are typically the largest part of a web page's total weight, so reducing them is one of the highest-impact optimisations available:

Page load speed — Largest Contentful Paint is often determined by the main image.
Search rankings — page experience signals include loading performance.
Bandwidth costs — smaller files mean less transfer to pay for.
Mobile experience — matters most on slower connections and metered data.
Conversions — slow pages are abandoned more often.

Frequently Asked Questions

How does this online image compressor work?

It decodes your image with the Canvas API and re-encodes it at your chosen quality, trying JPEG, WebP and PNG and keeping whichever result is smallest. If none of them beats your original file, the original is kept unchanged. All processing is local — your images never leave your device.

Why did another tool make my PNG bigger?

Because re-encoding a PNG through a canvas throws away the original's optimisations — indexed palette, reduced bit depth, stripped metadata — and writes a full 32-bit RGBA PNG instead. For an optimised graphic that can be several times larger. This tool compares every candidate against the original and never hands back a bigger file.

Does the quality slider affect PNG files?

Not directly — PNG is lossless, so a quality value has no meaning for it. To genuinely shrink a PNG the tool converts it to WebP or JPEG, which do respond to quality. If your PNG has transparency, WebP is chosen so the alpha channel is preserved.

Can I compress multiple images at once?

Yes. Select or drag several files onto the drop zone and they are processed as a batch, each with its own before and after sizes. Use Download All to save them in sequence.

Is this image compressor really free?

Completely free — no registration, no watermarks, no file limits, no subscription. It runs entirely in your browser and keeps working offline once the page has loaded.

Which formats are supported?

JPG/JPEG, PNG and WebP, in any mix within a single batch. WebP output depends on your browser supporting WebP encoding; where it isn't available the tool falls back to JPEG or PNG automatically.