LogWerk
LogWerk is a free, offline-first server log analyzer that runs in a web browser.
What LogWerk is
LogWerk is a free, offline-first server log analyzer that runs in a web browser. It is aimed at developers, sysadmins, and site operators who need traffic details without building a full log analytics stack. The tool recognizes Nginx and Apache formats automatically, while manual presets and custom regular expressions handle other layouts. It loads plain and gzip-compressed rotated logs. Its dashboard covers traffic over time, HTTP statuses, paths, client IPs, browsers, operating systems, referrers, and related measures. More than 70 known bots and crawlers are classified by provider and purpose, including AI crawlers, with crawler segmentation and crawl-waste reports. A Security tab flags listed attack patterns, suspicious IPs, 404 paths, and failed logins. Requests can be arranged into chronological sessions by IP address and user agent. Logs are parsed in the browser and are not uploaded, according to the maker; no account is required. Filtered results export to CSV, and the latest log is cached in IndexedDB for restoration after refresh. The interface supports six languages and the project uses the MIT license.
Good
- Automatically detects Nginx and Apache formats
- Classifies more than 70 bots and crawlers
- Security tab reports suspicious activity
- Groups requests into session timelines
- Exports filtered results as CSV
Watch out
- CDN resources require local vendoring for fully offline use
- Local JavaScript modules need a served folder
- Interface depends on a modern browser
Who it suits
LogWerk suits developers, sysadmins, and site operators examining server traffic locally. It is useful when you want browser-based analysis without an account or a full analytics stack.
Verdict
LogWerk combines traffic, crawler, security, and session analysis in a browser. Its local parsing, IndexedDB persistence, and CSV export fit privacy-focused log review, while setup details matter for offline use.
The facts
Each one read from LogWerk's own pages, with the date it was checked.
What it does
- Audience
- It is built for developers, sysadmins, and site operators.checked 8 Oct 2026
- Compressed logs
- It can load gzip-compressed and plain rotated log files in the browser.checked 8 Oct 2026
- Crawler analysis
- It classifies more than 70 known bots and crawlers by provider and purpose, including AI crawlers.checked 8 Oct 2026
- Export
- Users can export the currently filtered results as CSV.checked 8 Oct 2026
- Export and persistence
- It exports filtered results as CSV and caches the last loaded log in browser IndexedDB for restoration after refresh.checked 8 Oct 2026
- Integrations and dependencies
- The project loads Tailwind CSS, Chart.js, and Google Fonts from CDNs.checked 8 Oct 2026
- Intended users
- It is built for developers, sysadmins, and site operators who want to understand traffic without setting up a full log analytics stack.checked 8 Oct 2026
- Languages
- Its interface supports English, German, French, Spanish, Italian, and Ukrainian.checked 8 Oct 2026
- License
- The project is licensed under MIT, which permits use, copying, modification, distribution, sublicensing, and sale subject to its stated conditions.checked 8 Oct 2026
- Log formats
- It detects Nginx and Apache log formats automatically and also supports manual presets and custom regular expressions.checked 8 Oct 2026
- Offline use
- The maker says the interface loads resources from CDNs and recommends vendoring them locally for a fully offline build.checked 8 Oct 2026
- Privacy
- The maker says logs are parsed in the browser and never uploaded; no account is needed.checked 8 Oct 2026
- Purpose
- LogWerk is an offline-first server log analyzer that runs in a web browser.checked 8 Oct 2026
- Security analysis
- Its Security tab detects listed attack patterns and reports suspicious IPs, 404 paths, and failed logins.checked 8 Oct 2026
- Security features
- Its Security tab detects listed attack patterns and reports suspicious IPs, 404 paths, and failed logins.checked 8 Oct 2026
- Session analysis
- It groups requests by IP address and user agent into chronological session timelines.checked 8 Oct 2026
- Session journeys
- It groups requests by IP and user agent into chronological session timelines.checked 8 Oct 2026
- Setup limit
- The README says modern browsers restrict local JavaScript modules over file:// and recommends serving the folder from a local server; it also describes a Safari workaround.checked 8 Oct 2026
- Traffic analysis
- Its dashboard reports traffic over time, HTTP statuses, paths, client IPs, browsers, operating systems, referrers, and other traffic insights.checked 8 Oct 2026
- What it does
- LogWerk is an offline-first server log analyzer that runs in a web browser.checked 8 Oct 2026
Where it runs
- Browser storage
- The most recently loaded log is cached in IndexedDB and restored after a page refresh.checked 8 Oct 2026
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