Free Online Tool

Enlarge Image to 400 KB

Targets a 400 KB output. Adjust the target value in the tool below if needed.

100% Private

Instant Results

No Sign-up

Why Use Our Image Enlarger?

Browser-based, private, and instant.

True Upscaling

Re-renders your image at higher resolution to hit your target file size with quality detail.

100% Private

Your images never leave your device. All processing happens locally in your browser.

Instant Results

Browser-based processing means no waiting for uploads - get results in seconds.

Free Forever

No sign-ups, no limits, no watermarks. Completely free to use, always.

How It Works

Three simple steps to a larger image.

Upload Your Image

Select or drag and drop any JPG, PNG or WebP image.

Set Target Size

Enter a target file size larger than your original.

Download Enlarged

Download your enlarged, high-resolution image instantly.

Frequently Asked Questions

The tool upscales your image dimensions proportionally and re-encodes it at a higher quality JPEG setting to hit the target file size. This increases the file size while improving sharpness.

Yes - the tool renders at higher resolution and uses higher quality JPEG encoding. However, there is a natural limit to detail that can be reconstructed from a low-quality original.

You can enlarge up to 50 MB. The input file itself must be under 25 MB.

No. All processing happens entirely in your browser using WebAssembly. Your file never leaves your device.

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Enlarge Image to 400 KB – Increase Resolution & File Size Online

Our free image enlarger upscales your image dimensions and re-encodes it at higher JPEG quality to reach your target file size around 400 KB. Unlike simple resizing, the tool preserves aspect ratio while maximizing visual quality.

The entire process runs in your browser using WebAssembly - no server uploads, no privacy risk. Whether you need a larger image for print, social media, or platform requirements, the tool handles it in seconds.

Works with JPG, PNG, WebP, GIF, and BMP files up to 25 MB. Target sizes up to 50 MB are supported.