How to Use FileFlex

Step-by-step: convert an image

1. Open FileFlex at fileflex.app.
2. Add your images — drag them onto the drop area, or click to browse. You can add multiple files at once.
3. Choose your target format — WebP, JPEG, or PNG.
4. Set the quality — for WebP and JPEG, drag the slider between 10% and 100%. Higher = better looking, larger file.
5. Choose a scale — keep the original dimensions, or shrink them to 75%, 50%, or 25%.
6. Click "Convert & Download All" — each file is processed on your device. Single files download directly; multiple files are bundled into a ZIP.

Which format should I use?

WebP — best for websites and modern apps

WebP is a modern format developed by Google. At the same quality level, WebP files are typically 25–35% smaller than equivalent JPEGs, and it supports transparency like PNG. If you're publishing images to a website, WebP should be your default.

Best for: blog images, product photos, marketing assets, thumbnails, hero images.

JPEG — universal compatibility

JPEG has been the standard for photographs for decades. Every browser, app, and device can display it. It doesn't support transparency, and it's larger than WebP at the same visual quality — but it works everywhere without exception.

Best for: email attachments, print workflows, older systems, social media uploads.

PNG — lossless with transparency

PNG is a lossless format, meaning no image quality is lost during compression. It supports full transparency. The trade-off is size — PNG files are usually much larger than WebP or JPEG.

Best for: logos, icons, UI screenshots, images that need a transparent background, anything where pixel-perfect accuracy matters.

What quality setting should I choose?

• 100% — visually identical to the original; largest file.
• 85–90% — the sweet spot for most photos. Nearly indistinguishable from the original, but significantly smaller.
• 70–80% — good for web thumbnails and email.
• Below 60% — noticeable artifacts; only use for tiny thumbnails or previews.

Our default is 90%, which balances quality and file size well for most use cases.

Understanding the resize options

The Dimensions Scale dropdown shrinks both width and height proportionally:

• 100% — original dimensions unchanged.
• 75% — subtle shrink, good for reducing payloads without visible change.
• 50% — half-size; halves each dimension, so area is quartered.
• 25% — quarter-size; useful for thumbnails and previews.

Resizing is done with high-quality bilinear filtering, so you won't get jagged edges.

Frequently asked questions

Is there a file size limit?

No. The only limit is your browser's memory. Very large images (over 50 MB) may take a moment to process on older devices.

Are my images private?

Yes — completely. Your files never leave your device. Nothing is uploaded, stored, or transmitted anywhere. See our privacy policy for full details.

Can I convert multiple images at once?

Yes. Drop as many files as you like; they'll all be queued and processed together. Multiple files are bundled into a ZIP for download.

Does converting to WebP reduce quality?

At quality 85% or above, WebP is generally visually indistinguishable from the original. Below that, you may notice slight softening in fine details.

Which browsers are supported?

All modern browsers: Chrome, Firefox, Safari, and Edge — desktop and mobile. The tool works offline once the page is loaded.