diff --git a/test/libc/stdio/sscanf_test.c b/test/libc/stdio/sscanf_test.c
index e1408c09a..411f176b1 100644
--- a/test/libc/stdio/sscanf_test.c
+++ b/test/libc/stdio/sscanf_test.c
@@ -21,6 +21,7 @@
 #include "libc/intrin/bits.h"
 #include "libc/inttypes.h"
 #include "libc/limits.h"
+#include "libc/math.h"
 #include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/internal.h"
@@ -328,6 +329,114 @@ TEST(sscanf, flexdecimal_hex) {
   EXPECT_EQ(666, y);
 }
 
+TEST(sscanf, floating_point_simple) {
+  float x = 666.666f, y = x, z = y;
+  EXPECT_EQ(3, sscanf("0.3715 .3715 3715", "%f %f %f", &x, &y, &z));
+  EXPECT_EQ(0.3715f, x);
+  EXPECT_EQ(0.3715f, y);
+  EXPECT_EQ(3715.0f, z);
+}
+
+TEST(sscanf, floating_point_simple_double_precision) {
+  double x = 666.666, y = x, z = y;
+  EXPECT_EQ(3, sscanf("0.3715 .3715 3715", "%lf %lf %lf", &x, &y, &z));
+  EXPECT_EQ(0.3715, x);
+  EXPECT_EQ(0.3715, y);
+  EXPECT_EQ(3715.0, z);
+}
+
+TEST(sscanf, floating_point_nan) {
+  float a = 666.666f, b = a, c = b, d = c, e = d, f = e;
+  EXPECT_EQ(4, sscanf("nan -NAN nAn NaN", "%f %f %f %f", &a, &b, &c, &d));
+  EXPECT_EQ(2, sscanf("nan(2) -NaN(_ABCDzxcv1234_)", "%f %f", &e, &f));
+  EXPECT_TRUE(isnan(a));
+  EXPECT_TRUE(isnan(b));
+  EXPECT_TRUE(isnan(c));
+  EXPECT_TRUE(isnan(d));
+  EXPECT_TRUE(isnan(e));
+  EXPECT_TRUE(isnan(f));
+}
+
+TEST(sscanf, floating_point_nan_double_precision) {
+  double a = 666.666, b = a, c = b, d = c, e = d, f = e;
+  EXPECT_EQ(4, sscanf("nan -NAN nAn NaN", "%lf %lf %lf %lf", &a, &b, &c, &d));
+  EXPECT_EQ(2, sscanf("nan(2) -NAN(_ABCDzxcv1234_)", "%lf %lf", &e, &f));
+  EXPECT_TRUE(isnan(a));
+  EXPECT_TRUE(isnan(b));
+  EXPECT_TRUE(isnan(c));
+  EXPECT_TRUE(isnan(d));
+  EXPECT_TRUE(isnan(e));
+  EXPECT_TRUE(isnan(f));
+}
+
+TEST(sscanf, floating_point_infinity) {
+  float a = 666.666f, b = a, c = b, d = c, e = d, f = e, g = f;
+  EXPECT_EQ(4, sscanf("inf +INF -iNf InF", "%f %f %f %f", &a, &b, &c, &d));
+  EXPECT_EQ(3, sscanf("+infinity -INFINITY iNfInItY", "%f %f %f", &e, &f, &g));
+  EXPECT_TRUE(isinf(a));
+  EXPECT_TRUE(isinf(b));
+  EXPECT_TRUE(isinf(c));
+  EXPECT_TRUE(isinf(d));
+  EXPECT_TRUE(isinf(e));
+  EXPECT_TRUE(isinf(f));
+  EXPECT_TRUE(isinf(g));
+}
+
+TEST(sscanf, floating_point_infinity_double_precision) {
+  double a = 666.666, b = a, c = b, d = c, e = d, f = e, g = f;
+  EXPECT_EQ(4, sscanf("inf +INF -iNf InF", "%lf %lf %lf %lf", &a, &b, &c, &d));
+  EXPECT_EQ(3, sscanf("+infinity -INFINITY iNfInItY", "%lf %lf %lf", &e, &f, &g));
+  EXPECT_TRUE(isinf(a));
+  EXPECT_TRUE(isinf(b));
+  EXPECT_TRUE(isinf(c));
+  EXPECT_TRUE(isinf(d));
+  EXPECT_TRUE(isinf(e));
+  EXPECT_TRUE(isinf(f));
+  EXPECT_TRUE(isinf(g));
+}
+
+TEST(sscanf, floating_point_documentation_examples) {
+  float a = 666.666f, b = a, c = b, d = c, e = d, f = e, g = f, h = g, i = h;
+
+  EXPECT_EQ(2, sscanf("111.11 -2.22", "%f %f", &a, &b));
+  EXPECT_EQ(2, sscanf("Nan nan(2)", "%f %f", &c, &d));
+  EXPECT_EQ(1, sscanf("inF", "%f", &e));
+  EXPECT_EQ(2, sscanf("0X1.BC70A3D70A3D7P+6 1.18973e+4932zzz", "%f %f", &f, &g));
+  EXPECT_EQ(1, sscanf("-0.0000000123junk", "%f", &h));
+  EXPECT_EQ(1, sscanf("junk", "%f", &i));
+
+  EXPECT_EQ(111.11f, a);
+  EXPECT_EQ(-2.22f, b);
+  EXPECT_TRUE(isnan(c));
+  EXPECT_TRUE(isnan(d));
+  EXPECT_TRUE(isinf(e));
+  EXPECT_EQ(0X1.BC70A3D70A3D7P+6f, f);
+  EXPECT_TRUE(isinf(g));
+  EXPECT_EQ(-0.0000000123f, h);
+  EXPECT_EQ(.0f, i);
+}
+
+TEST(sscanf, floating_point_documentation_examples_double_precision) {
+  double a = 666.666f, b = a, c = b, d = c, e = d, f = e, g = f, h = g, i = h;
+
+  EXPECT_EQ(2, sscanf("111.11 -2.22", "%lf %lf", &a, &b));
+  EXPECT_EQ(2, sscanf("Nan nan(2)", "%lf %lf", &c, &d));
+  EXPECT_EQ(1, sscanf("inF", "%lf", &e));
+  EXPECT_EQ(2, sscanf("0X1.BC70A3D70A3D7P+6 1.18973e+4932zzz", "%lf %lf", &f, &g));
+  EXPECT_EQ(1, sscanf("-0.0000000123junk", "%lf", &h));
+  EXPECT_EQ(1, sscanf("junk", "%lf", &i));
+
+  EXPECT_EQ(111.11, a);
+  EXPECT_EQ(-2.22, b);
+  EXPECT_TRUE(isnan(c));
+  EXPECT_TRUE(isnan(d));
+  EXPECT_TRUE(isinf(e));
+  EXPECT_EQ(0X1.BC70A3D70A3D7P+6, f);
+  EXPECT_TRUE(isinf(g));
+  EXPECT_EQ(-0.0000000123, h);
+  EXPECT_EQ(.0, i);
+}
+
 TEST(sscanf, luplus) {
   long x = 666;
   EXPECT_EQ(1, sscanf("+123", "%lu", &x));