diff --git a/fasttld.go b/fasttld.go
index 034f2ed..08201d7 100644
--- a/fasttld.go
+++ b/fasttld.go
@@ -149,12 +149,12 @@ func (f *FastTLD) Extract(e URLParams) *ExtractResult {
 
 	// Check for IPv6 address
 	var netlocIsIPv6 bool
-	openingSquareBracketIdx := strings.IndexByte(netloc, '[')
+	openingSquareBracketIdx := indexFirstByteBefore(netloc, '[', endOfHostWithPortDelimitersSet)
 	if openingSquareBracketIdx > 0 {
 		// Erroneous opening square bracket
 		return &urlParts
 	}
-	closingSquareBracketIdx := strings.IndexByte(netloc, ']')
+	closingSquareBracketIdx := indexFirstByteBefore(netloc, ']', endOfHostWithPortDelimitersSet)
 	if openingSquareBracketIdx == 0 {
 		if !(closingSquareBracketIdx > 0 && isIPv6(netloc[1:closingSquareBracketIdx])) {
 			// Have opening square bracket but invalid IPv6 => Domain is invalid
diff --git a/fasttld_test.go b/fasttld_test.go
index ec7b844..546a4be 100644
--- a/fasttld_test.go
+++ b/fasttld_test.go
@@ -438,6 +438,7 @@ var domainOnlySingleTLDTests = []extractTest{
 }
 var pathTests = []extractTest{
 	{urlParams: URLParams{URL: "http://www.example.com/this:that"}, expected: &ExtractResult{Scheme: "http://", SubDomain: "www", Domain: "example", Suffix: "com", RegisteredDomain: "example.com", Path: "/this:that"}, description: "Colon in Path"},
+	{urlParams: URLParams{URL: "http://example.com/oid/[order_id]"}, expected: &ExtractResult{Scheme: "http://", Domain: "example", Suffix: "com", RegisteredDomain: "example.com", Path: "/oid/[order_id]"}, description: "Square brackets in Path"},
 }
 var wildcardTests = []extractTest{
 	{urlParams: URLParams{URL: "https://asdf.wwe.ck"},
diff --git a/strings.go b/strings.go
index 7e83e4a..4908dd3 100644
--- a/strings.go
+++ b/strings.go
@@ -147,6 +147,15 @@ func makeNewReplacerParams(toBeReplaced string, toReplaceWith string) []string {
 	return params
 }
 
+// indexFirstByteBefore returns the index of the first instance of byte b
+// before any byte in notAfterCharsSet, otherwise -1
+func indexFirstByteBefore(s string, b byte, notAfterCharsSet asciiSet) int {
+	if firstNotAfterCharIdx := indexAnyASCII(s, notAfterCharsSet); firstNotAfterCharIdx != -1 {
+		return strings.IndexByte(s[0:firstNotAfterCharIdx], b)
+	}
+	return strings.IndexByte(s, b)
+}
+
 // indexLastByteBefore returns the index of the last instance of byte b
 // before any byte in notAfterCharsSet, otherwise -1
 func indexLastByteBefore(s string, b byte, notAfterCharsSet asciiSet) int {