Log Viewer Online
Open a log file and read it as structured, searchable entries — free, and nothing is uploaded
Free Online Log Viewer
Open a log file and read it properly instead of squinting at a wall of text in a terminal. The viewer takes a file from your machine — or text you paste — and renders each line as a structured entry with its timestamp, severity, and message pulled out. From there you can jump straight to the errors, search for a request ID or a hostname, and step through what happened in order. It reads application logs, JSON lines, syslog, and web server access logs, detecting the format automatically. The file is opened by the browser itself and never sent anywhere, so you can read a production log containing customer addresses or tokens without it leaving your laptop.
Key Features
- Open a .log, .txt, or .json file directly from your machine — no upload step
- Automatic format detection for JSON lines, syslog, plain text, and access logs
- Every line broken out into timestamp, severity, and message
- Jump to just the errors or warnings with one click on the severity badges
- Full-text search across the opened file to trace a request ID or user
- Export what you are looking at to JSON, CSV, or plain text
- Runs entirely in your browser — the file is never transmitted or stored
- Free, with no sign-up and no file count limit
Common Use Cases
- Opening a log file a colleague sent you without installing a desktop viewer
- Reading a production log that contains tokens or personal data, safely
- Following one request through a noisy service log by searching its ID
- Skimming an overnight batch job to see whether anything failed
- Viewing a JSON-lines log where every entry is an unreadable single line
- Checking a log quickly from a machine where you cannot install software
Frequently Asked Questions
How do I view a log file online?
Click Open log file and pick the file from your machine, or paste the contents into the box. The viewer parses it immediately and shows each line as a structured entry you can filter and search. Nothing is uploaded — the file is read by your browser.
Is it safe to open a production log here?
Yes. The file is read locally through the browser file API and parsed with JavaScript on your device. It is never sent to a server, so IP addresses, session tokens, and customer data in the log stay on your machine.
What log formats can the viewer open?
JSON lines, syslog, Apache and Nginx access logs, and general timestamped plain text. The format is detected automatically from the content, so you do not need to pick one. For a specific web server format there are dedicated pages for Apache, Nginx, and access logs.
How large a log file can I open?
Files up to 25 MB open comfortably. Above that the viewer declines the file rather than freezing the tab — split the log with split or tail, or paste the section you care about.
Is this log viewer free?
Yes, and there is no account. Because the parsing happens in your browser instead of on our servers, there is no cost per file and therefore no paid tier or quota.
What is the difference between the viewer and the log analyzer?
They share the same engine. The viewer is aimed at opening a file and reading through it, so it leads with the file picker. The analyzer pages are aimed at a specific server format and explain the fields that format records.
Related Tools
- Log File AnalyzerThe general analyzer — JSON, syslog, and plain text as well.
- Access Log AnalyzerFind 4xx and 5xx failures in any web server access log.
- Apache Log AnalyzerParse the Common and Combined Log Formats Apache writes.
- Nginx Log AnalyzerParse Nginx access.log and error.log in the combined format.