diff --git a/NEWS b/NEWS
index 080a2060d4..80e92f41ac 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,8 @@ Major new features:
   wcstoll, wcstoul, wcstoull, wcstol_l, wcstoll_l, wcstoul_l,
   wcstoull_l, wcstoimax, wcstoumax, wcstoq, wcstouq.
 
+* PRIb* and PRIB* macros from C2X have been added to <inttypes.h>.
+
 Deprecated and removed features, and other changes affecting compatibility:
 
   [Add deprecations, removals and changes affecting compatibility here]
diff --git a/manual/stdio.texi b/manual/stdio.texi
index d7eab1843a..d89b6b2040 100644
--- a/manual/stdio.texi
+++ b/manual/stdio.texi
@@ -1829,7 +1829,7 @@ output, but are different when used with @code{scanf} for input
 Print an integer as an unsigned binary number.  @samp{%b} uses
 lower-case @samp{b} with the @samp{#} flag and @samp{%B} uses
 upper-case.  @samp{%b} is an ISO C2X feature; @samp{%B} is an
-extension recommended by ISO C2X.  @xref{Integer Conversions}, for
+optional ISO C2X feature.  @xref{Integer Conversions}, for
 details.
 
 @item @samp{%o}
diff --git a/stdio-common/tst-printf-binary-main.c b/stdio-common/tst-printf-binary-main.c
index e94b8b5959..0784368d85 100644
--- a/stdio-common/tst-printf-binary-main.c
+++ b/stdio-common/tst-printf-binary-main.c
@@ -16,6 +16,7 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <inttypes.h>
 #include <limits.h>
 #include <stdio.h>
 #include <string.h>
@@ -77,6 +78,58 @@ do_test (void)
 		"10000111011001010100001100100001", "%lB",
 		0xfedcba9987654321ul);
 #endif
+  CHECK_PRINTF ("0b11", "%#" PRIb8, (uint8_t) 3);
+  CHECK_PRINTF ("0b11", "%#" PRIb16, (uint16_t) 3);
+  CHECK_PRINTF ("0b10000111011001010100001100100001", "%#" PRIb32,
+		(uint32_t) 0x87654321);
+  CHECK_PRINTF ("0b11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIb64,
+		(uint64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0b11", "%#" PRIbLEAST8, (uint_least8_t) 3);
+  CHECK_PRINTF ("0b11", "%#" PRIbLEAST16, (uint_least16_t) 3);
+  CHECK_PRINTF ("0b10000111011001010100001100100001", "%#" PRIbLEAST32,
+		(uint_least32_t) 0x87654321);
+  CHECK_PRINTF ("0b11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIbLEAST64,
+		(uint_least64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0b11", "%#" PRIbFAST8, (uint_fast8_t) 3);
+  CHECK_PRINTF ("0b11", "%#" PRIbFAST16, (uint_fast16_t) 3);
+  CHECK_PRINTF ("0b10000111011001010100001100100001", "%#" PRIbFAST32,
+		(uint_fast32_t) 0x87654321);
+  CHECK_PRINTF ("0b11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIbFAST64,
+		(uint_fast64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0b10000111011001010100001100100001", "%#" PRIbPTR,
+		(uintptr_t) 0x87654321);
+  CHECK_PRINTF ("0b11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIbMAX,
+		(uintmax_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0B11", "%#" PRIB8, (uint8_t) 3);
+  CHECK_PRINTF ("0B11", "%#" PRIB16, (uint16_t) 3);
+  CHECK_PRINTF ("0B10000111011001010100001100100001", "%#" PRIB32,
+		(uint32_t) 0x87654321);
+  CHECK_PRINTF ("0B11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIB64,
+		(uint64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0B11", "%#" PRIBLEAST8, (uint_least8_t) 3);
+  CHECK_PRINTF ("0B11", "%#" PRIBLEAST16, (uint_least16_t) 3);
+  CHECK_PRINTF ("0B10000111011001010100001100100001", "%#" PRIBLEAST32,
+		(uint_least32_t) 0x87654321);
+  CHECK_PRINTF ("0B11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIBLEAST64,
+		(uint_least64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0B11", "%#" PRIBFAST8, (uint_fast8_t) 3);
+  CHECK_PRINTF ("0B11", "%#" PRIBFAST16, (uint_fast16_t) 3);
+  CHECK_PRINTF ("0B10000111011001010100001100100001", "%#" PRIBFAST32,
+		(uint_fast32_t) 0x87654321);
+  CHECK_PRINTF ("0B11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIBFAST64,
+		(uint_fast64_t) 0xfedcba9987654321ull);
+  CHECK_PRINTF ("0B10000111011001010100001100100001", "%#" PRIBPTR,
+		(uintptr_t) 0x87654321);
+  CHECK_PRINTF ("0B11111110110111001011101010011001"
+		"10000111011001010100001100100001", "%#" PRIBMAX,
+		(uintmax_t) 0xfedcba9987654321ull);
   CHECK_PRINTF (" 1010", "%5b", 10u);
   CHECK_PRINTF (" 1010", "%5B", 10u);
   CHECK_PRINTF ("01010", "%05b", 10u);
diff --git a/stdlib/inttypes.h b/stdlib/inttypes.h
index a5fa97b7c8..0ace21f54d 100644
--- a/stdlib/inttypes.h
+++ b/stdlib/inttypes.h
@@ -164,6 +164,45 @@ typedef wchar_t __gwchar_t;
 # define PRIxPTR	__PRIPTR_PREFIX "x"
 # define PRIXPTR	__PRIPTR_PREFIX "X"
 
+/* Binary notation.  */
+# if __GLIBC_USE (ISOC2X)
+#  define PRIb8		"b"
+#  define PRIb16	"b"
+#  define PRIb32	"b"
+#  define PRIb64	__PRI64_PREFIX "b"
+
+#  define PRIbLEAST8	"b"
+#  define PRIbLEAST16	"b"
+#  define PRIbLEAST32	"b"
+#  define PRIbLEAST64	__PRI64_PREFIX "b"
+
+#  define PRIbFAST8	"b"
+#  define PRIbFAST16	__PRIPTR_PREFIX "b"
+#  define PRIbFAST32	__PRIPTR_PREFIX "b"
+#  define PRIbFAST64	__PRI64_PREFIX "b"
+
+#  define PRIbMAX	__PRI64_PREFIX "b"
+#  define PRIbPTR	__PRIPTR_PREFIX "b"
+
+#  define PRIB8		"B"
+#  define PRIB16	"B"
+#  define PRIB32	"B"
+#  define PRIB64	__PRI64_PREFIX "B"
+
+#  define PRIBLEAST8	"B"
+#  define PRIBLEAST16	"B"
+#  define PRIBLEAST32	"B"
+#  define PRIBLEAST64	__PRI64_PREFIX "B"
+
+#  define PRIBFAST8	"B"
+#  define PRIBFAST16	__PRIPTR_PREFIX "B"
+#  define PRIBFAST32	__PRIPTR_PREFIX "B"
+#  define PRIBFAST64	__PRI64_PREFIX "B"
+
+#  define PRIBMAX	__PRI64_PREFIX "B"
+#  define PRIBPTR	__PRIPTR_PREFIX "B"
+# endif
+
 
 /* Macros for scanning format specifiers.  */
 
