File & Pathflags: i

Video File Extension

Match common video file extensions: mp4, mov, avi, mkv, webm, m4v, flv, wmv, mpg, mpeg.

Available in

JavaScript / ECMAScript code

jsJavaScript

const re = new RegExp("\\.(mp4|mov|avi|mkv|webm|m4v|flv|wmv|mpg|mpeg)$", "i");
const input = "movie.mp4";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));

Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).

Python (re) code

pyPython

import re

pattern = re.compile(r"\.(mp4|mov|avi|mkv|webm|m4v|flv|wmv|mpg|mpeg)$", re.IGNORECASE)
input_text = "movie.mp4"
for m in pattern.finditer(input_text):
    print(m.group(0))

Stdlib `re` module — no third-party dependency. Works on Python 3.6+.

Go (RE2) code

goGo

package main

import (
	"fmt"
	"regexp"
)

func main() {
	re := regexp.MustCompile(`(?i)\.(mp4|mov|avi|mkv|webm|m4v|flv|wmv|mpg|mpeg)$`)
	input := `movie.mp4`
	for _, match := range re.FindAllString(input, -1) {
		fmt.Println(match)
	}
}

Uses `regexp.MustCompile` (panics on bad patterns at startup) and `FindAllString` for all matches.

Pattern

regexengine-agnostic

\.(mp4|mov|avi|mkv|webm|m4v|flv|wmv|mpg|mpeg)$   (flags: i)

Raw source: \.(mp4|mov|avi|mkv|webm|m4v|flv|wmv|mpg|mpeg)$

How it works

\. matches the literal dot. The alternation covers the most common video container formats. The trailing $ anchors to end-of-string so we don't match `.mp4` mid-filename. The i flag makes matching case-insensitive (.MOV, .Mp4, etc.).