Regex Tester — Online Match, Replace & Split for Perl, C#, sed, Bash, Go, grep, PowerShell & Ruby
Regex Tester
Regex tester — match, replace & split
Free online regex tester for Perl, C#, sed, bash, Go/Golang, grep, PowerShell, and Ruby-style workflows. Paste a pattern, test string, and see results instantly.
| # | Index | Match | Groups |
|---|---|---|---|
| 1 | 8 | alice@example.com | — |
| 2 | 29 | bob@asli.dev | — |
Sample tests
Load a sample to quickly test regex patterns — useful when comparing Perl, sed, bash, or C# workflows.
Language & tool flavors
Perl regex tester, test regex C#, sed / bash / grep, Go golang regex test, PowerShell, and Ruby notes — how to run the same idea in each environment.
Perl regex tester notes — m//, s///, and qr// for match/replace workflows.
- Test with: perl -ne 'print if /pattern/'
- Replace: s/pattern/repl/g — like this page’s Replace mode.
- Use (?i) inline or /i for case-insensitive Perl test regex runs.
if ($text =~ /(?i)\berror\b/) {
$text =~ s/\berror\b/ALERT/gi;
}Regex Tester for Perl, C#, sed, Bash, Go & More
Free online regex tester with match, replace, and split. Use it as a Perl regex tester, sed regex tester, bash regex tester, or to test regex C# and Go / golang regex test patterns before shipping code.
Frequently asked questions
- What is a regex tester?
- A regex tester lets you paste a regular expression and a sample string, then instantly see matches, replacements, or split parts — useful before you run the same pattern in Perl, C#, sed, bash, Go, grep, PowerShell, or Ruby.
- Can I use this as a Perl regex tester?
- Yes. Match and Replace modes mirror common Perl m// and s/// workflows. The Perl flavor tab shows how to perl-test regex patterns on the command line.
- Does this help test regex C# patterns?
- Yes. Use Match/Replace here, then copy the pattern into Regex.Matches or Regex.Replace in C#. The C# tab covers flags and verbatim strings for test regex C# work.
- Is this a sed or bash regex tester?
- Replace mode is a practical online stand-in for sed -E 's/pat/repl/g'. Bash and grep tabs explain [[ =~ ]] and grep -E so you can validate before a shell regex tester run.
- Can I go / golang regex test here?
- You can prototype patterns interactively, then adapt them for Go’s RE2 regexp package. Note: Go lacks lookbehind and backreferences — the Go tab calls out those limits.
Whether you need a regex perl tester, regex sed tester, grep regex tester, or a powershell / ruby regex tester, validate the pattern here first. Then copy the same idea into sed -E, grep -E, [[ =~ ]], Regex.Replace, or regexp.MustCompile for a confident go regex test in production.