When you need to convert an image, dozens of websites offer to do it for free. But have you ever hesitated before uploading a personal photo, a client's design, or a confidential work document? That hesitation is smart. Understanding the difference between how online converters work is the key to keeping your files safe and private.
The biggest difference comes down to one simple question: is your file processed on their computer (a server) or on your own computer (in your browser)?
Most online tools use server-side processing. You upload your file, their server converts it, and then you download the result. While this can work, it comes with significant privacy and security risks.
A modern, more secure approach is browser-based (or "client-side") processing. This is the method FastConverter uses for all its tools. Your file is never uploaded or sent anywhere. All the work happens directly on your own device.
| Feature | Server-Side Converter | Browser-Based Converter (FastConverter) |
|---|---|---|
| File Privacy | File is uploaded to a third-party server. | File never leaves your device. 100% private. |
| Speed | Slow; depends on upload/download speed. | Instant; no uploads required. |
| Security | Potential risk of data breaches on the server. | Highly secure; your data is never transmitted. |
| Offline Use | Requires a constant internet connection. | Works offline after the page has been loaded. |
Experience the difference for yourself. Convert an image without ever uploading it.
Our tools use built-in web technologies to act as a self-contained piece of software running on your machine:
Yes, absolutely. Because your file is never uploaded, there is zero risk of it being intercepted, stored, or misused by a third party. It's the digital equivalent of editing a document on your own personal computer versus emailing it to a stranger to edit for you. For more on protecting your information online, see these tips from the FTC.
For the vast majority of images, the process is so fast you won't notice it. For extremely large images (e.g., over 50 megapixels), it might take a few seconds, but it only uses a small fraction of your computer's resources and only for the moment of conversion.
There is no catch. Because we don't have to pay for expensive servers to process and store user files, we can offer our tools for free. Our operational costs are significantly lower, and we pass those savings on to you.
Now that you know the difference, you can make an informed decision. While server-side tools may be necessary for highly complex, specialized tasks, for everyday image conversions, a browser-based tool like FastConverter offers an unbeatable combination of speed, security, and complete privacy.
