Image Compressor
Reduce JPEG, PNG, and WebP file sizes directly in your browser. Adjust quality, preview the result, and download — nothing is uploaded to any server.
What this tool does
The Kodivio Image Compressor reduces the file size of your images by applying lossy or lossless compression in your browser. You set a quality level, see an instant before/after preview, and download the result. No account, no upload, no waiting.
Beyond shrinking files, the tool strips EXIF metadata (GPS location, camera model, timestamps) automatically — useful when sharing images publicly or sending them via email. You can also convert between formats: for example, converting a heavy JPEG to WebP often cuts the file size by an additional 25–35% with no visible difference.
Who uses it
Web developers & designers
Optimizing images before deploying a site is one of the easiest wins for page speed. Smaller images load faster, improving Core Web Vitals and SEO without any code changes.
Bloggers & content teams
WordPress and similar platforms don't always compress images well. Running photos through this tool before uploading avoids the platform's auto-compression from degrading your images unpredictably.
Anyone sharing photos
Sending a 6 MB photo by email or messaging app can be slow and wasteful. Compressing to under 500 KB makes it instantly shareable — and removes location metadata in the process.
How to compress an image
- 1
Upload your image
Click the upload area or drag a file into it. JPEG, PNG, and WebP are supported. The original image loads into the editor — nothing is sent anywhere.
- 2
Set the quality level
The quality slider controls how aggressively the file is compressed. At 80–85%, most photos are visually identical to the original but significantly smaller. Lower values save more space but may introduce visible artifacts, especially around edges.
- 3
Choose an output format
Keep the original format, or switch to WebP for better compression, or PNG to preserve transparency. The preview updates immediately so you can compare.
- 4
Check the before/after preview
The side-by-side view shows the original and compressed versions at the same zoom level. Look for any visible quality loss before proceeding — particularly around text, logos, and high-contrast edges.
- 5
Download
Click Download. The compressed file saves directly to your device. The new file size is shown so you know exactly how much you saved.
Lossy vs. lossless — which should you use?
The right choice depends on your image type and how it will be used.
Lossy compression
Permanently removes image data that's difficult for the human eye to detect — color variation in smooth gradients, fine detail in shadows, and so on. File size reduction is substantial, often 60–80%.
Best for: Photos, social media images, blog posts, email attachments, any image where a small quality trade-off is acceptable.
Watch out for: Artifacts around high-contrast edges (text on images, logos) at high compression levels.
Lossless compression
Reorganizes file data more efficiently without discarding any pixels. The decompressed image is bit-for-bit identical to the original. File size reduction is smaller, typically 10–30%.
Best for: Logos, illustrations, UI assets, screenshots with text, any image where pixel-perfect accuracy matters.
Watch out for: Smaller savings than lossy — don't expect dramatic file size reductions on already-optimized PNGs.
Choosing the right format
| Format | Best for | Transparency | Browser support |
|---|---|---|---|
| JPEG | Photos, complex imagery | No | Universal |
| PNG | Logos, screenshots, text-heavy images | Yes | Universal |
| WebP | Everything — best compression ratio | Yes | All modern browsers |
WebP isn't supported on IE11 or very old Safari versions. If your audience includes legacy browsers, keep JPEG or PNG as a fallback using the HTML <picture> element.
Quality setting reference
Not sure where to set the slider? Here's a practical guide.
Near-lossless
Virtually no visible difference from the original. Use for print, archival, or any image that will be re-edited later.
Recommended for web
The sweet spot for most use cases. Photos look sharp, file sizes drop significantly, and the savings are meaningful for page load speed.
Aggressive compression
Noticeably smaller files. Artifacts may appear around fine detail and sharp edges. Fine for thumbnails and previews; less ideal for full-size display.
Avoid for most uses
Quality degradation becomes obvious. Useful only for very small thumbnails or low-bandwidth contexts where appearance is secondary to speed.
Tips for better results
Crop before compressing
Remove unnecessary areas first. Fewer pixels to compress means a smaller output file, and you keep compression budget for the parts that matter.
Use WebP for new projects
If you're building or updating a website and don't need to support IE11, WebP is almost always the best choice. It matches JPEG quality at significantly smaller sizes.
Don't compress images that are already compressed
Applying lossy compression to an already-lossy JPEG stacks artifacts. If you have the original file, always start from that.
Pre-compress before uploading to social platforms
LinkedIn, Facebook, and Instagram apply their own compression on upload. If you compress first at a quality you control, the platform's second pass has less to destroy.
Check text and logo areas closely in the preview
Lossy compression tends to blur sharp edges. If your image includes text or a logo, zoom into those areas in the preview before committing to a quality level.
Image size and website performance
Images are typically the largest assets on a web page — often accounting for more than half of the total page weight. Large images delay the browser's ability to display the main content, which affects a metric called Largest Contentful Paint (LCP). LCP measures how quickly the biggest visible element (usually a hero image or above-the-fold photo) loads.
Google uses LCP as one of its Core Web Vitals — a set of signals that directly influence search rankings. A slow LCP score (above 2.5 seconds) can push a page down in results, even if the content itself is strong. Compressing images is one of the most impactful changes you can make, and unlike code optimizations, it requires no technical changes to your site.
Beyond SEO, smaller images also improve the experience on slow connections and mobile data plans — which is where a large share of web traffic still comes from.
Privacy by design
Most online image compressors require your file to be uploaded to a remote server for processing. That means your image travels across the internet, is handled by someone else's infrastructure, and may be retained for analytics, training, or storage purposes.
This tool runs entirely in your browser. Your image is processed locally using the Canvas API — no network request is made, Kodivio receives nothing, and the image is cleared from memory when you close the tab. This matters especially if you're compressing anything sensitive: personal photos, internal documents, or images that contain private information.
Limitations worth knowing
- !Lossless compression savings vary widely. An already-optimized PNG may only shrink by a few percent — there's no magic beyond what the format allows.
- !HEIC files are not currently supported. Convert them to JPEG or PNG first using your device's built-in export options.
- !Very large files (20 MB+) may be slow to process on older or low-memory devices. This is a browser memory constraint.
- !Batch compression (multiple files at once) is not supported in the current version. Process files one at a time.
- !The quality slider applies to lossy formats. For lossless PNG compression, the slider has no effect — compression is always maximum.
Frequently asked questions
Will compressing reduce visible quality?
At 75–85% quality, most people can't spot the difference from the original. At lower settings, you may see blurring or blockiness around edges and detail areas.
Is my image uploaded to a server?
No. All processing happens in your browser. Nothing is transmitted, and Kodivio never receives your file.
Which format gives the smallest file?
WebP almost always wins for photos and graphics. JPEG is the safest for broad compatibility. PNG is best when you need transparency.
Does the tool remove EXIF data?
Yes. EXIF metadata — including GPS location, timestamps, and camera information — is stripped automatically during compression.
What quality setting should I use?
75–85% is the recommended range for web images. For print or archival use, stay at 90%+. For small thumbnails, you can safely go to 60%.
How does this help my website's SEO?
Smaller images load faster, improving Largest Contentful Paint (LCP) — a Core Web Vital that influences Google search rankings.