diff --git a/libc/stdio/printf.c b/libc/stdio/printf.c
index 23c6cde..5cc3391 100644
--- a/libc/stdio/printf.c
+++ b/libc/stdio/printf.c
@@ -188,7 +188,7 @@ int printf(const char* restrict format, ...) {
 		} else if (*format == '1') {
 			format++;
 			uint64_t i = (uint64_t) va_arg(parameters, uint64_t);
-			u64toa(i, buffer, 16);
+			u64toa(i, buffer, 10);
 			size_t len = strlen(buffer);
 			if (maxrem < len) {
 				// TODO: Set errno to EOVERFLOW.
@@ -198,6 +198,30 @@ int printf(const char* restrict format, ...) {
 				return -1;
 			written += len;
 		} else if (*format == '2') {
+			format++;
+			uint64_t i = (uint64_t) va_arg(parameters, uint64_t);
+			u64toa(i, buffer, 16);
+			size_t len = strlen(buffer);
+			if (maxrem < len) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(buffer, len))
+				return -1;
+			written += len;
+		} else if (*format == '3') {
+			format++;
+			int64_t i = (int64_t) va_arg(parameters, int64_t);
+			s64toa(i, buffer, 10);
+			size_t len = strlen(buffer);
+			if (maxrem < len) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(buffer, len))
+				return -1;
+			written += len;
+		} else if (*format == '4') {
 			format++;
 			int64_t i = (int64_t) va_arg(parameters, int64_t);
 			s64toa(i, buffer, 16);