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Free Image-Compressor Tool: Shrink Photos 90% in Seconds

Shrink photos, screenshots, and graphics to a fraction of their size without shipping them to a server. Compress, convert between formats, and resize to exact pixel dimensions all in one pass, all inside your own browser tab.

Try our free image-compressor tool to shrink JPG, PNG & WebP files by up to 90% instantly in your browser. No uploads, no signup  compress now.

✓ Free to use   ✓ No sign-up   ✓ Processed locally in your browser   ✓ Mobile friendly

Files never leave your device
No server upload
Multiple images at once
JPG · PNG · WebP
Before / after comparison
ZIP download
Drop images to optimize
or click below to browse your files
JPG · PNG · WebP — multiple files supported
80%
Higher quality means a larger file. PNG output is lossless, so this has no effect on PNG.
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Original size
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Result size
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Original image before processing
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Processed image after compression, conversion, or resizing
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Why images stay on your device

Built for privacy first, using your browser’s own image processing engine.

Nothing is uploaded

Compression, conversion, and resizing run through the HTML5 Canvas API in your browser. Your image files are not sent to a Bloxstation server or any third party.

No upload wait

Since files never travel over the network, processing starts immediately after you drop them in, limited only by your device's own speed.

Built by Bloxstation

Made by the team behind Bloxstation's laptop, phone, and web performance coverage, for the same everyday workflow we use ourselves.

Batch-first workflow

Drop in dozens of files at once and process the whole batch with a single quality or resize setting, instead of opening one image at a time.

No plugins, no installs

There's nothing to download, no browser extension to trust, and no desktop app to keep updated. Open the page and it's ready to use.

Who this tool is for

A general-purpose optimizer for anyone who deals with images regularly.

Bloggers & WordPress site owners

Shrink featured images and in-post screenshots before uploading, so pages load faster and Core Web Vitals scores hold up under Google's page experience checks.

Online sellers

Compress product photos for Shopify, Etsy, or a marketplace listing without blowing past upload size limits or waiting minutes for a page to save.

Social media managers

Resize a single graphic into a square post, a 1080×1350 portrait crop, and a 1080×1920 story in a few clicks using the built-in social presets.

How to compress an image

Four steps — everything happens on your device.

1. Upload

Drag and drop or select one or more JPG, PNG, or WebP images.

2. Choose settings

Pick a quality level, output format, or target dimensions.

3. Process

Your browser compresses, converts, or resizes each image.

4. Download

Save each image individually, or grab everything as a ZIP.

JPG vs PNG vs WebP vs AVIF

Which format should you use? A quick comparison.

FormatBest forTransparencyTypical size
JPGPhotos, blog featured imagesNoMedium
PNGLogos, screenshots, flat-color graphicsYesLarge (lossless)
WebPGeneral web use, Core Web VitalsYesSmall
AVIFMaximum compression, where browser support allowsYesSmallest

If you’re not sure where to start, WebP at 75–85% quality is a safe default for almost any photo or graphic headed to the web. Switch to PNG only when you need a transparent background or perfectly crisp edges on flat-color art like logos and icons.

How image compression works

A short, honest explanation of what this tool actually does.

This tool draws each uploaded image onto an HTML canvas at your chosen dimensions, then re-encodes it using your browser’s built-in JPG, PNG, WebP, or AVIF encoder. Lossy formats like JPG, WebP, and AVIF let you trade visual detail for a smaller file by adjusting the quality slider — most photos still look sharp at 70–85% quality. PNG output from this tool is always lossless, so its file size depends on image complexity rather than a quality setting.

Because encoding runs in the canvas rather than reading the file’s raw bytes, EXIF and other metadata is not carried over to the output — the tool corrects visual orientation first so rotated phone photos still display right-side up, but embedded metadata itself is not preserved.

Under the hood, the two levers that matter most are quality and dimensions. Quality controls how aggressively a lossy encoder discards fine detail; dimensions control the raw pixel count the encoder has to work with in the first place. Cutting an image’s width and height in half typically shrinks the file far more than any quality slider alone — which is why the Resize tab exists alongside Compress rather than being an afterthought.

Why compress images before uploading to WordPress

Smaller images mean a faster site.

Large, unoptimized images are one of the most common causes of slow-loading WordPress pages, and page speed affects both visitor experience and how search engines evaluate a page. Compressing an image before you upload it to your media library reduces the file WordPress has to store and serve, which can improve metrics like Largest Contentful Paint. Resizing an image to the dimensions it will actually display at — rather than uploading a full-resolution camera photo — often has an even bigger impact than compression alone.

The same logic applies well beyond WordPress. Email newsletters render faster and are less likely to get clipped by size limits. Slide decks and PDFs stay under attachment caps. Portfolio and photography sites feel snappier on mobile data. Anywhere an image travels over a network before it’s seen, a smaller file means less waiting for the person on the other end.

Frequently asked questions

Upload one or more JPG, PNG, or WebP images, choose a quality level and output format on the Compress tab, then click Compress all. Download the results individually or as a ZIP.

Yes — free to use with no account and no watermark. The only practical limit is how much memory your own browser and device have available for processing.

No. Every image is compressed, converted, and resized directly in your browser using the Canvas API. Files are not transmitted to Bloxstation or anyone else.

You can upload and output JPG, PNG, and WebP. AVIF output appears automatically as an option in browsers that support encoding it. Animated GIF is not supported, because canvas-based processing would flatten an animation to a single static frame.

WebP typically produces a smaller file size than JPG or PNG at comparable visual quality and has broad browser support, which is why it’s the recommended default here. AVIF can compress further where supported.

For JPG, WebP, and AVIF, you control the quality level — most images look visually close to the original at 70–85% quality while being noticeably smaller. PNG output is lossless, so quality is unaffected regardless of the slider.

Yes. Upload as many images as your browser can comfortably handle, process them together, and download them individually or all at once as a ZIP file.

Yes. The default Fit mode scales the image to stay within your target dimensions while preserving its aspect ratio — it will never stretch your image. Crop mode fills the exact target dimensions by trimming the edges instead.

Yes, as a side effect of canvas-based processing. Visual orientation from phone cameras is corrected before processing, but EXIF and other embedded metadata is not carried through to the output file.

Yes. The layout is responsive and works in modern mobile browsers, including uploading photos directly from your camera roll.

There’s a generous per-file size ceiling and a batch limit designed to keep the tool responsive, but for typical photos and graphics you’re unlikely to hit either. The practical constraint is your own device’s available memory — very large batches on low-memory devices may process more slowly.

This can happen when a quality setting is too high for a lossy format, or when converting a small, already-optimized file to PNG, which is lossless and doesn’t shrink flat-color images the way JPG or WebP can. Try a lower quality slider or a different output format — the tool will flag it if the result grows.

Ready to compress your images?

Free to use, and your files never leave your browser.

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