Server logs are the most honest record of what a system actually did, but raw logs are unreadable at scale: thousands of lines, each dense with addresses, timestamps, and codes. The first questions are always the same — how much traffic, how many errors, who is asking most, and which statuses dominate — and answering them should not require uploading logs to a third party or learning a query language. This tool parses pasted Apache and Nginx-style lines entirely in your browser, counts status codes, identifies the busiest IP, and computes the error rate, while counting unparsed lines honestly instead of dropping them.
Quick Answer: Enter a few log lines with 200, 404, and 500 statuses and the tool returns parsed counts, the top IP, and a 66.7% error rate for that sample.
Free Online Tool
Server Log Analyzer
Paste Apache/Nginx-style log lines and get status-code counts, top IPs, and the error rate — fully offline.
Logs never leave your browser. Lines without a recognizable status code are counted as unparsed, not silently dropped.
How to Use the Server Log Analyzer
- Enter your input in the tool above — for example, a few log lines with 200, 404, and 500 statuses.
- Choose any options the tool offers, such as the conversion direction or the settings that fit your case.
- Click the main button to run the tool and read the result it displays.
- Check the result against what you expected, then adjust the input and run it again if needed.
- Copy the output into your own document, code, or configuration wherever you need it.
Worked Example
Try it with a few log lines with 200, 404, and 500 statuses: the tool returns parsed counts, the top IP, and a 66.7% error rate for that sample. That example is a good first test whenever you use the tool, because it confirms you entered the input in the expected format before you trust it with your real values. This tool is built for triaging incidents, verifying deploys, and spotting abusive traffic, and the worked example shows the shape of a correct result so you can recognize a wrong one at a glance.
Key Features
- Runs entirely in your browser — nothing you type is uploaded anywhere.
- Built for triaging incidents, verifying deploys, and spotting abusive traffic, with the result shown immediately and in full.
- No account, no sign-up, and no software to install.
- Clear error messages when an input is incomplete or in the wrong format.
- Free to use as often as you like, for study, work, or checking homework.
Best Practices and Tips
- Start with the worked example in the guide, then substitute your own values.
- Double-check units and formats before trusting a result — most tool errors are input errors.
- Keep a note of the exact inputs that produced a result you rely on, so you can reproduce it.
- For anything important, cross-check with a second method or a known test value.
- Bookmark the tool if you use it regularly, so the same workflow is always one click away.
Common Mistakes to Avoid
- Treating unparsed lines as zero: they may hide the most interesting requests.
- Judging health by total lines alone, which mixes real users with bots and health checks.
- Copying a result without checking it against a known example first.
- Assuming the tool knows your context — it only sees the values you enter.
When This Tool Helps — and When It Doesn’t
This tool helps most when you need a fast, checkable answer for triaging incidents, verifying deploys, and spotting abusive traffic and you can verify the result against a known example. It does not replace professional judgment: for decisions with real consequences, treat the output as one input among several, verify it independently, and remember that the tool can only work with exactly what you enter. Used that way — quick check, verified result, human decision — it saves time without creating false confidence.
Frequently Asked Questions
What log formats does this support?
Common Apache and Nginx combined-style lines: an IP address, followed by the request in quotes and a three-digit status code. Lines without a recognizable status code are counted as unparsed rather than guessed at.
Do my logs leave my browser?
No. Parsing runs entirely on your device. Logs often contain IPs and paths you should not upload casually, which is exactly why this tool works offline.
What error rate should worry me?
It depends on the service, but a sudden jump from baseline matters more than any absolute number. A stable 1% of 404s from old links is normal; a spike to 20% after a deploy is a rollback signal.