diff --git a/defaults.go b/defaults.go
index 9fc3bc81..b5f6b61d 100644
--- a/defaults.go
+++ b/defaults.go
@@ -123,76 +123,6 @@ func (dns *Msg) SetEdns0(udpsize uint16, do bool) *Msg {
 	return dns
 }
 
-// IsRcode checks if the header of the packet has rcode set.
-func (dns *Msg) IsRcode(rcode int) (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Rcode == rcode
-	return
-}
-
-// IsQuestion returns true if the packet is a question.
-func (dns *Msg) IsQuestion() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Response == false
-	return
-}
-
-// IsRcodeFormatError checks if the message has FormErr set.
-func (dns *Msg) IsRcodeFormatError() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Rcode == RcodeFormatError
-	return
-}
-
-// IsUpdate checks if the message is a dynamic update packet.
-func (dns *Msg) IsUpdate() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Opcode == OpcodeUpdate
-	ok = ok && dns.Question[0].Qtype == TypeSOA
-	return
-}
-
-// IsNotify checks if the message is a valid notify packet.
-func (dns *Msg) IsNotify() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Opcode == OpcodeNotify
-	ok = ok && dns.Question[0].Qclass == ClassINET
-	ok = ok && dns.Question[0].Qtype == TypeSOA
-	return
-}
-
-// IsAxfr checks if the message is a valid axfr request packet.
-func (dns *Msg) IsAxfr() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Opcode == OpcodeQuery
-	ok = ok && dns.Question[0].Qclass == ClassINET
-	ok = ok && dns.Question[0].Qtype == TypeAXFR
-	return
-}
-
-// IsIXfr checks if the message is a valid ixfr request packet.
-func (dns *Msg) IsIxfr() (ok bool) {
-	if len(dns.Question) == 0 {
-		return false
-	}
-	ok = dns.MsgHdr.Opcode == OpcodeQuery
-	ok = ok && dns.Question[0].Qclass == ClassINET
-	ok = ok && dns.Question[0].Qtype == TypeIXFR
-	return
-}
-
 // IsTsig checks if the message has a TSIG record as the last record
 // in the additional section.
 func (dns *Msg) IsTsig() (ok bool) {