Detect Log4Shell (CVE-2021-44228) payloads and check Log4j versions — defensive, detection-only.
What log4shell does
log4shell.tools is a free online toolkit built around one job — Log4Shell Scanner — with a handful of closely related tools alongside it. There is no software to install, no account to create, and no watermark on anything you produce. Upload your file, let us do the work, and download the result.
The full toolset: Log4Shell Scanner · Log4j Version Checker.
How your files are handled
Your privacy matters. Uploaded files are processed on our servers and stored securely only as long as needed for you to download your result — they are automatically deleted after 7 days. We never sell, share, or use your files for any purpose other than performing the conversion you asked for.
Free, forever
Every tool on log4shell is free to use. We keep the interface clean and fast so you can get in, convert, and get on with your day. Questions? See our FAQ or the help page, and explore our guides to learn more about the formats we work with.