diff --git a/lib/cf-h1-proxy.c b/lib/cf-h1-proxy.c
index a85cd1d5a6..f29c8f0865 100644
--- a/lib/cf-h1-proxy.c
+++ b/lib/cf-h1-proxy.c
@@ -31,7 +31,6 @@
 #include "http.h"
 #include "http1.h"
 #include "http_proxy.h"
-#include "url.h"
 #include "select.h"
 #include "progress.h"
 #include "cfilters.h"
@@ -39,7 +38,6 @@
 #include "connect.h"
 #include "curl_trc.h"
 #include "strcase.h"
-#include "transfer.h"
 #include "curlx/strparse.h"
 
 
diff --git a/lib/cf-socket.c b/lib/cf-socket.c
index 3e47a98722..ee771fc0fe 100644
--- a/lib/cf-socket.c
+++ b/lib/cf-socket.c
@@ -55,7 +55,6 @@
 #endif
 
 #include "urldata.h"
-#include "bufq.h"
 #include "curl_trc.h"
 #include "if2ip.h"
 #include "cfilters.h"
diff --git a/lib/conncache.c b/lib/conncache.c
index 869af4215e..a865959709 100644
--- a/lib/conncache.c
+++ b/lib/conncache.c
@@ -34,9 +34,6 @@
 #include "conncache.h"
 #include "curl_share.h"
 #include "sigpipe.h"
-#include "connect.h"
-#include "select.h"
-#include "curlx/strparse.h"
 
 
 #define CPOOL_IS_LOCKED(c)    ((c) && (c)->locked)
diff --git a/lib/cookie.c b/lib/cookie.c
index 19d8fc8547..819b8b1027 100644
--- a/lib/cookie.c
+++ b/lib/cookie.c
@@ -38,7 +38,6 @@
 #include "parsedate.h"
 #include "curlx/strdup.h"
 #include "llist.h"
-#include "bufref.h"
 #include "curlx/strparse.h"
 
 /* number of seconds in 400 days */
diff --git a/lib/curl_share.c b/lib/curl_share.c
index 3ff2755684..338727a4fa 100644
--- a/lib/curl_share.c
+++ b/lib/curl_share.c
@@ -24,7 +24,6 @@
 #include "curl_setup.h"
 
 #include "urldata.h"
-#include "connect.h"
 #include "curl_share.h"
 #include "vtls/vtls.h"
 #include "vtls/vtls_scache.h"
diff --git a/lib/doh.c b/lib/doh.c
index e22fde8ef4..5c36e1c7e8 100644
--- a/lib/doh.c
+++ b/lib/doh.c
@@ -35,7 +35,7 @@
 #include "connect.h"
 #include "curlx/strdup.h"
 #include "curlx/dynbuf.h"
-#include "escape.h"
+#include "escape.h"  /* for Curl_hexencode() */
 #include "urlapi-int.h"
 
 #define DNS_CLASS_IN 0x01
diff --git a/lib/ftp.c b/lib/ftp.c
index a7be74846a..809d7fa4ba 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -49,7 +49,6 @@
 #include "transfer.h"
 #include "escape.h"
 #include "ftp.h"
-#include "fileinfo.h"
 #include "ftplistparser.h"
 #include "curl_range.h"
 #include "strcase.h"
diff --git a/lib/http_proxy.c b/lib/http_proxy.c
index e9dfb8dbb3..a9521c92da 100644
--- a/lib/http_proxy.c
+++ b/lib/http_proxy.c
@@ -34,7 +34,6 @@
 #include "cf-h1-proxy.h"
 #include "cf-h2-proxy.h"
 #include "connect.h"
-#include "transfer.h"
 #include "vauth/vauth.h"
 #include "curlx/strparse.h"
 
diff --git a/lib/pingpong.c b/lib/pingpong.c
index a2ca05ae47..572aec78c0 100644
--- a/lib/pingpong.c
+++ b/lib/pingpong.c
@@ -27,6 +27,10 @@
 #include "curl_setup.h"
 
 #include "urldata.h"
+#include "pingpong.h"
+
+#ifdef USE_PINGPONG
+
 #include "cfilters.h"
 #include "connect.h"
 #include "multiif.h"
@@ -34,9 +38,6 @@
 #include "curl_trc.h"
 #include "select.h"
 #include "progress.h"
-#include "pingpong.h"
-
-#ifdef USE_PINGPONG
 
 /* Returns timeout in ms. 0 or negative number means the timeout has already
    triggered */
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 1b1fb6cced..f27dff9f4f 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -24,8 +24,6 @@
 #include "curl_setup.h"
 
 #include "urldata.h"
-#include "curl_trc.h"
-#include "progress.h"
 #include "ratelimit.h"
 
 #define CURL_US_PER_SEC         1000000
diff --git a/lib/sendf.c b/lib/sendf.c
index f2d30a4269..fcb67933d3 100644
--- a/lib/sendf.c
+++ b/lib/sendf.c
@@ -42,7 +42,6 @@
 #include "cw-out.h"
 #include "cw-pause.h"
 #include "multiif.h"
-#include "strerror.h"
 #include "progress.h"
 
 static void cl_reset_writer(struct Curl_easy *data)
diff --git a/lib/socks.c b/lib/socks.c
index 67e9c9b3c7..e983d29d11 100644
--- a/lib/socks.c
+++ b/lib/socks.c
@@ -41,7 +41,6 @@
 #include "connect.h"
 #include "socks.h"
 #include "curlx/inet_pton.h"
-#include "url.h"
 
 /* for the (SOCKS) connect state machine */
 enum socks_state_t {
diff --git a/lib/telnet.c b/lib/telnet.c
index f14aa9c9be..c89e94e9f9 100644
--- a/lib/telnet.c
+++ b/lib/telnet.c
@@ -51,7 +51,6 @@
 #include "transfer.h"
 #include "sendf.h"
 #include "curl_trc.h"
-#include "connect.h"
 #include "progress.h"
 #include "arpa_telnet.h"
 #include "select.h"
diff --git a/lib/transfer.c b/lib/transfer.c
index 183aee0f84..71914e13cf 100644
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -68,7 +68,6 @@
 #include "getinfo.h"
 #include "multiif.h"
 #include "connect.h"
-#include "mime.h"
 #include "hsts.h"
 #include "setopt.h"
 #include "headers.h"
diff --git a/lib/url.c b/lib/url.c
index b085df1a4d..3c0d913432 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -65,9 +65,7 @@
 #include <iphlpapi.h>
 #endif
 
-#include "doh.h"
 #include "urldata.h"
-#include "formdata.h"
 #include "mime.h"
 #include "bufref.h"
 #include "vtls/vtls.h"