Compress Studio

Image Compressor

A free online image compressor: batch-compress JPG, PNG and WebP files with a quality, longest-side or target file size. Compare before and after with a draggable slider, then download. Everything runs inside your browser — no upload, no sign-up.

中文 EN

🖼 Batch ready 🎯 Target size 🔒 Stays local

Drop images here, or click to choose

JPG / PNG / WebP / GIF / AVIF — pick several at once, or just paste a screenshot with Ctrl + V

＋ Choose images

Compression settings

The four presets cover most cases. Switch the compression mode or adjust the longest side when you need finer control.

Preset

Mode

Output quality 75%

Higher keeps more detail and produces a bigger file. 75% is the usual "visually lossless" sweet spot.

Longest side

Larger images are scaled down proportionally, never up. "Original" is capped at 3000px to keep the browser responsive.

Output format

JPG is the safest choice; WebP is usually another 20–30% smaller.

🔒 Images are processed on your device only — nothing is uploaded.

✍ What this image compressor does

This is a fully client-side image compressor for the classic "your file is too large" problem: a CMS upload that keeps failing, a landing page that loads too slowly, an email attachment over the limit, or a form that only accepts images under 2 MB. It re-encodes your pictures through the browser's Canvas API, so files never leave your device and you never need an account.

Using it takes three steps: drag images into the drop zone (or pick them, or paste a screenshot), choose a preset or set quality and longest side manually, then hit compress. Every file reports its before/after size, dimensions and saving percentage. Click "compare" to drag a divider across the image and judge the quality yourself, then download one file or all of them. Up to 30 images per batch makes batch image compression painless for asset clean-ups and client deliveries.

When a platform has a hard limit, switch to target-size mode: type 200 KB or 500 KB and the tool binary-searches the quality between 20% and 100% to land just under it. Resizing often beats lowering quality — phone photos start around 4000px, and scaling to 1920px cuts the file dramatically while looking identical on screen. For another 20–30% saving at the same visual quality, switch the output format to WebP.

A note on "compressing without losing quality": true lossless compression can only strip metadata, so the saving is small. What you get here is visual losslessness — the default 75% quality at 1920px is indistinguishable on phones and laptops. For print or further retouching, choose the HD preset or push quality above 90%.

🎯 Which preset to pick

HD · 90% / 2560px

Quality first. Photography, product hero shots and anything you plan to edit again.

Standard · 75% / 1920px

The everyday choice for blog images, newsletters and web banners — usually a 70%+ reduction.

Data saver · 60% / 1280px

Smaller files for chat, email attachments and upload forms where the image is only viewed.

Tiny · 40% / 800px

Thumbnails, avatars and list previews — often down to a few dozen KB.

💡 Tips

Resize before you squeeze quality: dropping to 1920px usually saves far more than 75% → 60%.
Transparent PNGs get a white background when exported as JPG — pick WebP or PNG to keep transparency.
Re-compressing an already optimized image often makes it bigger; the tool flags it as "not smaller".
For large batches, resize first and then fine-tune the target size for the few that still fail.
Nothing is written to disk: original files and results live in page memory and disappear on refresh.

❓ FAQ

Are my images uploaded anywhere?

No. Decoding, resizing and re-encoding all happen in your browser with the Canvas API. The image data never touches the network, and the tool keeps working if you go offline after the page loads.

Why did the file get bigger?

The source may already be a highly optimized WebP or JPG, so re-encoding adds overhead. The tool marks it as "not smaller" and you can simply keep the original, or lower the quality / longest side and try again.

Which formats are supported?

Input: anything the browser can decode — JPG, PNG, WebP, AVIF, GIF (first frame). Output: JPG, WebP or PNG. PNG ignores the quality setting, so it only shrinks through resizing.

Is EXIF data removed?

Yes. Re-encoding keeps only pixels, so camera model and GPS metadata are dropped — which is usually exactly what you want before sharing a photo.

Does it work on mobile?

Yes. Tap "Choose images" to pick from the gallery; the layout adapts to portrait screens and the drag-to-compare slider works with touch.

🔒 Privacy

No image is uploaded or collected. All processing happens on your device, results live in page memory and vanish when you close or refresh the tab. Your last used settings are stored in localStorage only, so the tool can restore them next time.

📈 Usage

Total sessions: 77