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Shapes

Upscale imageslocally

100% Client-side

0 Storage

Hosted in France

Free

Understand

Local image upscaler, without AI dependency

The FileVert enlargement tool allows you to increase the resolution of your images (JPG, PNG, WebP, AVIF) directly in your browser. Unlike online AI-based upscalers, no files are sent to a server and no external model analyzes your visuals. Resizing is performed locally, with deterministic, predictable and documented algorithms.

What "in your browser" means

  • No files are sent to a server
  • No remote storage
  • No external access to your data
  • Works even offline
After the tool

Send the result: standard mode or Explore mode

When your file is ready on your device, send it with FileVert Transfer from the built-in send action. Choose whether the recipient downloads immediately (standard) or previews first in the browser without a silent local copy (Explore mode).

Standard mode

Secure link: the recipient downloads the file in the usual way. Best for final deliverables, archives and heavy attachments.

Guide: send very large files

Explore mode

Share images to flip through in a grid or fullscreen before any download decision.

Guide: photo gallery in the browser

100% local

No data sent

Folder processing

Controlled quality, up to 4×

Enlargement features

Enlarge your images with professional quality.

Enlargement up to 4× with high-quality interpolation

Professional interpolation algorithm for sharp and detailed results.

Batch processing and complete folders

Upscale multiple images simultaneously or import a complete folder.

Strictly preserved folder structure

Your folder structure is preserved when downloading.

Supported formats: JPG, PNG, WebP, AVIF

Full support for modern image formats.

Works offline

Once the page is loaded, enlargement works without network.

No AI, no learning, no semantic alteration of images

Deterministic algorithms, predictable and controllable results.

Local upscale vs online AI upscaling

No upload

No proprietary models

No artificial detail reconstruction

No cloud dependency

Controllable, reproducible result

PRIVACY

Privacy & sobriety

Your images never leave your computer

100% local processing in your browser

No data sent to our servers

Responsible alternative to AI-based upscale services

0 Data stored

All processing is done locally in your browser.

Our other tools

Prepare your files with our other free, local tools.

Image Compressor

Reduce the weight of your images without visible quality loss.

Use

Audio Compressor

Convert and compress audio files locally, with no server upload.

Use

PDF Optimizer

Compress and optimize your PDF documents instantly.

Use

Natural integration with FileVert

Once your images are enlarged, transfer them immediately via FileVert.

Start a transfer

Frequently asked questions

Everything you need to know about FileVert Image Upscaler

All operations are performed locally in your browser. No files are sent to a server.
No. Enlargement relies on deterministic interpolation algorithms, without AI models or machine learning.
Yes. You can process multiple images simultaneously or import a complete folder, with folder structure preservation.
JPEG, PNG, WebP and AVIF, both input and output.
Up to 4×, with a quality/sharpness compromise optimized for web and light printing.
No. No storage, no logs, no retention.
Yes. Once the page is loaded, enlargement works without network.

Free image enlargement and resolution improvement tool, 100% local in browser, no registration, no AI, to prepare your files before sending, web publishing or archiving.