MAC Address (Colon-Separated, Case-Insensitive) Regex for Go
/^[0-9a-fA-F]{2}(?::[0-9a-fA-F]{2}){5}$/What this pattern does
This page provides a well-structured, multi-part regular expression for matching mac address (colon-separated, case-insensitive), ported and verified for Go. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Go project — whether you're validating in a Gin handler, a gRPC service, or a command-line tool.
Go Implementation
// MAC Address (Colon-Separated, Case-Insensitive)
// ReDoS-safe | RegexVault — Web & Network > MAC Address
package validation
import "regexp"
var macAddressColonseparatedCaseinsensitiveRe = regexp.MustCompile(`^[0-9a-fA-F]{2}(?::[0-9a-fA-F]{2}){5}$`)
func ValidateMacAddressColonseparatedCaseinsensitive(s string) bool {
return macAddressColonseparatedCaseinsensitiveRe.MatchString(s)
}
// Example
// fmt.Println(ValidateMacAddressColonseparatedCaseinsensitive("00:1A:2B:3C:4D:5E")) // trueTest Cases
Matches (Valid) | Rejects (Invalid) |
|---|---|
00:1A:2B:3C:4D:5E | 00:1a:2b:3c:4d |
00:1a:2b:3c:4d:5e | 00:1a:2b:3c:4d:5e:6f |
FF:FF:FF:FF:FF:FF | 00-1a-2b-3c-4d-5e |
A0:B1:C2:D3:E4:F5 | GG:HH:II:JJ:KK:LL |
01:23:45:AB:CD:EF | 001a2b3c4d5e |
When to use this pattern
This pattern is drawn from the Web & Network > MAC Address category and carries a ReDoS-safe certification. That matters for Go developers because Go's RE2 engine is inherently safe from catastrophic backtracking, but this pattern has been additionally verified for correctness. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.
Common Pitfalls
The i flag approach ([0-9a-f]{2} with /i) also works but makes the character class semantics less explicit.
Technical Notes
Preferred for input validation where user-submitted MAC addresses may be in mixed case. Normalize to lowercase before storage.
Have a pattern that belongs in the vault?
Submit it for review — community-verified patterns get credited to your GitHub handle. Free submissions join the queue. Priority review available for $15.
Submit a Pattern