Log Entry (Common Log Format) Regex Pattern

Live Regex Tester

Pattern Breakdown

Code Examples

const regex = /^(\S+)\s+(\S+)\s+(\S+)\s+\[([^\]]+)\]\s+"(\S+)\s+(\S+)\s+(\S+)"\s+(\d+)\s+(\d+)/gm;
const test = "127.0.0.1 - - [07/Mar/2026:14:00:00 +0000] "GET /index.html HTTP/1.1" 200 1234";
console.log(regex.test(test)); // true

// Extract matches
const matches = test.match(regex);
console.log(matches);

import re

pattern = r'^(\S+)\s+(\S+)\s+(\S+)\s+\[([^\]]+)\]\s+"(\S+)\s+(\S+)\s+(\S+)"\s+(\d+)\s+(\d+)'
test = "127.0.0.1 - - [07/Mar/2026:14:00:00 +0000] "GET /index.html HTTP/1.1" 200 1234"
match = re.findall(pattern, test)
print(match)  # Found!

package main

import (
    "fmt"
    "regexp"
)

func main() {
    re := regexp.MustCompile(`^(\S+)\s+(\S+)\s+(\S+)\s+\[([^\]]+)\]\s+"(\S+)\s+(\S+)\s+(\S+)"\s+(\d+)\s+(\d+)`)
    fmt.Println(re.MatchString("127.0.0.1 - - [07/Mar/2026:14:00:00 +0000] "GET /index.html HTTP/1.1" 200 1234")) // true
}

Common Use Cases

Match Examples

About the Log Entry (Common Log Format) Regex

Parses Apache/Nginx Common Log Format entries, extracting IP, timestamp, method, path, status code, and bytes.

Regular expressions (regex) are powerful pattern matching tools used across virtually all programming languages. The log entry (common log format) pattern is classified as advanced difficulty in the data formats category. It works in all major programming languages.

When using this regex, always consider edge cases and test thoroughly with real-world data. Use the interactive tester above to validate the pattern against your specific inputs before deploying to production.

More Data Formats Patterns