Are my images uploaded to a server?

No. All compression happens entirely inside your browser using the HTML5 Canvas API. Your images never leave your device and are never sent to any server.

What formats are supported?

You can compress JPEG, PNG, WebP, GIF, and BMP files. For output, you can keep the original format or convert to JPEG, PNG, or WebP. GIF and BMP are always converted to one of those three since they cannot be re-encoded natively by the browser.

Why is my PNG larger after compression?

PNG is a lossless format - the browser always encodes it at full quality. If you want a smaller file from a PNG source, switch the output format to JPEG or WebP, which support lossy quality control.

What quality setting should I use for web images?

For most web use, a quality of 75–85 provides an excellent balance between visual quality and file size. JPEG artifacts become noticeable below 60. WebP typically achieves better quality-to-size ratios than JPEG at the same quality setting.

What does "Max dimension" do?

Setting a max dimension (e.g. 1920 px) scales the image down so neither the width nor height exceeds that value, preserving the aspect ratio. This is useful for photos straight from a camera or phone that may be 4000+ pixels wide.

Does compression remove EXIF data like GPS location?

Yes. The browser Canvas API does not preserve EXIF metadata, so GPS coordinates, camera model, and other EXIF tags are stripped from the output - which also helps reduce file size and protect privacy.

Can I compress multiple images at once?

Yes. Drop or select multiple files. Each image is processed in sequence and shown with before/after size information. You can download individual files or click "Download All as ZIP" to get everything in one archive.

What is the file size limit?

There is no hard limit imposed by this tool, but very large files (over 50 MB) may cause memory issues depending on your browser and device. The tool will warn you for files over that threshold.

Image Compressor - Toolcroft

Core Web Vitals: why image size matters

Image optimization directly impacts Largest Contentful Paint (LCP), the Google Core Web Vital that measures how quickly the main content of a page loads. LCP is often the largest single optimization opportunity on image-heavy pages. Google's Page Experience ranking signal uses LCP, so large unoptimized images directly affect SEO and user experience. Target LCP under 2.5 seconds for a "Good" rating.

Next-gen format adoption

Modern formats provide dramatically better compression than JPEG and PNG:

WebP: supported by 97%+ of browsers worldwide (Can I Use, 2024). Production-ready with no fallback needed for most audiences. 25–35% smaller than JPEG at equivalent quality.
AVIF: supported by ~90% of browsers (Chrome 85+, Firefox 113+, Safari 16.4+). Up to 50% smaller than JPEG. Encoding is slower, making it better suited for pre-processed assets than real-time compression.

For new projects, WebP is the practical choice today. For maximum compression and modern browser targets, AVIF is the future.

How browser-based image compression works

This tool compresses your images using the HTML5 Canvas API, which is built into every modern browser. When you drop an image, the browser decodes it into raw pixels, draws those pixels onto an invisible canvas, then re-encodes the canvas as a JPEG or WebP with the quality level you specify. The result is a new file that is often 40–80% smaller with minimal visible quality loss.

Because compression runs entirely client-side, your images are never uploaded to any server. This makes the tool faster than server-based compressors and completely private, even when processing large batches on your CPU and GPU.

Best quality settings for web images

For most web use cases, a quality setting of 75–85 provides an excellent balance between file size and visual fidelity. Here are some guidelines:

Quality 85–100: Near-lossless; use for professional photography, print preparation, or images where artifacts would be noticeable.
Quality 70–84: Best for e-commerce product images, blog photos, and hero images where load time matters.
Quality 50–69: Good for thumbnails, background images, and content where quality is less critical.
Quality below 50: Visible compression artifacts; only use where extreme file size reduction is required (e.g., email attachments).

JPEG vs WebP vs PNG

Choosing the right format can be just as important as the quality setting:

JPEG: The most widely supported format. Excellent for photographs and images with gradients. Does not support transparency.
WebP: A modern format developed by Google that achieves 25–35% better compression than JPEG at the same visual quality. Supports transparency. Supported by all major browsers since 2020.
PNG: Lossless compression. Use for images that contain text, sharp edges, logos, or transparency. File sizes are typically larger than JPEG or WebP for photographs.

Recommendation: Switch images from JPEG to WebP using this tool to get the same visual quality at a significantly smaller file size, with no quality change required.

How to remove EXIF data from photos

EXIF (Exchangeable Image File Format) metadata is embedded in JPEG and other image files by cameras and smartphones. It can contain:

GPS coordinates: exact location where the photo was taken
Camera make, model, and serial number
Date and time the photo was captured
Lens settings (aperture, shutter speed, ISO)

When this tool recompresses an image using the Canvas API, EXIF data is not preserved in the output; it is automatically stripped. This happens because the canvas only stores raw pixel data, not the original file's metadata container. This is useful for protecting privacy before sharing photos online.