diff --git a/README b/README
index c795553..7cf28bf 100644
--- a/README
+++ b/README
@@ -13,14 +13,13 @@ program, which can be used to encrypt a password with crypt(3).
 
 
 The canonical distribution point for releases of the program is
-http://ftp.debian.org/debian/pool/main/w/whois/ .
+https://ftp.debian.org/debian/pool/main/w/whois/ .
 
 
 Useful information sources:
-- http://www.ripe.net/ripe/docs/current-ripe-documents/ripe-database-documents
-- http://www.iana.org/domains/root/db/
-- http://www.icann.org/en/resources/idn/fast-track/string-evaluation-completion
-- http://www.aftld.org/
+- https://www.ripe.net/ripe/docs/current-ripe-documents/ripe-database-documents
+- https://www.iana.org/domains/root/db/
+- https://www.icann.org/en/resources/idn/fast-track/string-evaluation-completion
+- https://www.aftld.org/
 
 Marco d'Itri <md@linux.it>
-
diff --git a/as_del_list b/as_del_list
index 625090a..24cb377 100644
--- a/as_del_list
+++ b/as_del_list
@@ -1,4 +1,4 @@
-# http://www.iana.org/assignments/as-numbers
+# https://www.iana.org/assignments/as-numbers
 
 248	251	ripe
 306	371	whois.nic.mil
diff --git a/ip6_del_list b/ip6_del_list
index a9ab644..d28d2f1 100644
--- a/ip6_del_list
+++ b/ip6_del_list
@@ -1,4 +1,4 @@
-# http://www.iana.org/assignments/ipv6-unicast-address-assignments
+# https://www.iana.org/assignments/ipv6-unicast-address-assignments
 # The parser is very simple-minded and wants the two first components of
 # addresses. It does not deal with networks == 0 or > 24 bit.
 
diff --git a/ip_del_list b/ip_del_list
index a5ca170..fcbb4a9 100644
--- a/ip_del_list
+++ b/ip_del_list
@@ -4,7 +4,7 @@
 # unless they are very big and contains multiple assignments to different
 # customers documented in the whois database.
 #
-# http://www.iana.org/assignments/ipv4-address-space
+# https://www.iana.org/assignments/ipv4-address-space
 #
 0.0.0.0/8	UNKNOWN
 1.0.0.0/8	apnic
diff --git a/po/es.po b/po/es.po
index 24d15ee..744ba82 100644
--- a/po/es.po
+++ b/po/es.po
@@ -20,13 +20,13 @@
 # los siguientes documentos:
 #
 #   - El proyecto de traducción de Debian al español
-#     http://www.debian.org/intl/spanish/
+#     https://www.debian.org/intl/spanish/
 #     especialmente las notas y normas de traducción en
-#     http://www.debian.org/intl/spanish/notas
+#     https://www.debian.org/intl/spanish/notas
 #
 #   - La guía de traducción de po's de debconf:
 #     /usr/share/doc/po-debconf/README-trans
-#     o http://www.debian.org/intl/l10n/po-debconf/README-trans
+#     o https://www.debian.org/intl/l10n/po-debconf/README-trans
 #
 msgid ""
 msgstr ""
diff --git a/tld_serv_list b/tld_serv_list
index d216974..238cf5a 100644
--- a/tld_serv_list
+++ b/tld_serv_list
@@ -1,4 +1,4 @@
-# http://www.iana.org/domains/root/db/
+# https://www.iana.org/domains/root/db/
 #
 # Domain names MUST be lowercase and MUST begin with "." or "-".
 # First match wins.
diff --git a/whois.1 b/whois.1
index 580c891..d6bdc7e 100644
--- a/whois.1
+++ b/whois.1
@@ -289,7 +289,7 @@ will be queried.
 WHOIS Protocol Specification.
 .P
 .IR "RIPE Database Query Reference Manual" :
-.RI < http://www.ripe.net/data\-tools/support/documentation/ripe\-database\-query\-reference\-manual >
+.RI < https://www.ripe.net/data\-tools/support/documentation/ripe\-database\-query\-reference\-manual >
 .SH BUGS
 The program may have buffer overflows in the command line parser:
 be sure to not pass untrusted data to it.
diff --git a/whois.c b/whois.c
index c4b9742..5c3a979 100644
--- a/whois.c
+++ b/whois.c
@@ -1503,7 +1503,7 @@ int isasciidigit(const char c)
     return (c >= '0' && c <= '9') ? 1 : 0;
 }
 
-/* http://www.ripe.net/ripe/docs/databaseref-manual.html */
+/* https://www.ripe.net/ripe/docs/databaseref-manual.html */
 
 void NORETURN usage(int error)
 {