diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt
index 53a9168ba7d8959e65c2442f6a078155d6f24c71..1686a54d22a746036b997d6eb8d5b85ca1d79c5d 100644
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -134,6 +134,7 @@ The placeholders are:
 - '%C(...)': color specification, as described in color.branch.* config option
 - '%m': left, right or boundary mark
 - '%n': newline
+- '%%': a raw '%'
 - '%x00': print a byte from a hex code
 - '%w([<w>[,<i1>[,<i2>]]])': switch line wrapping, like the -w option of
   linkgit:git-shortlog[1].
diff --git a/Documentation/technical/api-strbuf.txt b/Documentation/technical/api-strbuf.txt
index a0e0f850f83fe164dd7c1ca87d001fe485ba2ec2..3b1da10f263dad08ad327d678da9ada32c83599f 100644
--- a/Documentation/technical/api-strbuf.txt
+++ b/Documentation/technical/api-strbuf.txt
@@ -199,6 +199,10 @@ character if the letter `n` appears after a `%`.  The function returns
 the length of the placeholder recognized and `strbuf_expand()` skips
 over it.
 +
+The format `%%` is automatically expanded to a single `%` as a quoting
+mechanism; callers do not need to handle the `%` placeholder themselves,
+and the callback function will not be invoked for this placeholder.
++
 All other characters (non-percent and not skipped ones) are copied
 verbatim to the strbuf.  If the callback returned zero, meaning that the
 placeholder is unknown, then the percent sign is copied, too.
diff --git a/daemon.c b/daemon.c
index 5783e2401108adb1fef6943ef80bd78dbc76ecad..51d9d6b8acfeb445ea9854e9ce8dcff23050d20e 100644
--- a/daemon.c
+++ b/daemon.c
@@ -147,7 +147,6 @@ static char *path_ok(char *directory)
 			{ "IP", ip_address },
 			{ "P", tcp_port },
 			{ "D", directory },
-			{ "%", "%" },
 			{ NULL }
 		};
 
diff --git a/strbuf.c b/strbuf.c
index a6153dca278abe957254fa091fdcd8eb13b90b25..6cbc1fcfd86e45c85fda079f8bce8895adbcb3a4 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -227,6 +227,12 @@ void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 			break;
 		format = percent + 1;
 
+		if (*format == '%') {
+			strbuf_addch(sb, '%');
+			format++;
+			continue;
+		}
+
 		consumed = fn(sb, format, context);
 		if (consumed)
 			format += consumed;
diff --git a/t/t6006-rev-list-format.sh b/t/t6006-rev-list-format.sh
index 571931588eda5799efbf2b0789abd10b8770a0a7..b0047d3c6b593795561ce908ab8e10ff574d3dbc 100755
--- a/t/t6006-rev-list-format.sh
+++ b/t/t6006-rev-list-format.sh
@@ -19,6 +19,13 @@ test_cmp expect.$1 output.$1
 "
 }
 
+test_format percent %%h <<'EOF'
+commit 131a310eb913d107dd3c09a65d1651175898735d
+%h
+commit 86c75cfd708a0e5868dc876ed5b8bb66c80b4873
+%h
+EOF
+
 test_format hash %H%n%h <<'EOF'
 commit 131a310eb913d107dd3c09a65d1651175898735d
 131a310eb913d107dd3c09a65d1651175898735d