diff --git a/apps/memcached/memcache.cc b/apps/memcached/memcache.cc
index 115aa0ed4..f61af22a6 100644
--- a/apps/memcached/memcache.cc
+++ b/apps/memcached/memcache.cc
@@ -650,7 +650,7 @@ class cache {
 
         ss << "size: " << _cache.size() << "\n";
         ss << "buckets: " << _cache.bucket_count() << "\n";
-        ss << "load: " << to_sstring_sprintf((double)_cache.size() / _cache.bucket_count(), "%.2lf") << "\n";
+        ss << "load: " << sprint("%.2lf", (double)_cache.size() / _cache.bucket_count()) << "\n";
         ss << "max bucket occupancy: " << max_size << "\n";
         ss << "bucket occupancy histogram:\n";
 
diff --git a/core/sstring.hh b/core/sstring.hh
index df151bb0d..b2b21f0d7 100644
--- a/core/sstring.hh
+++ b/core/sstring.hh
@@ -584,7 +584,7 @@ static String make_sstring(Args&&... args)
 template <typename string_type, typename T>
 inline
 string_type to_sstring_sprintf(T value, const char* fmt) {
-    char tmp[sizeof(value) * 3 + 3];
+    char tmp[sizeof(value) * 3 + 2];
     auto len = std::sprintf(tmp, fmt, value);
     using char_type = typename string_type::value_type;
     return string_type(reinterpret_cast<char_type*>(tmp), len);
@@ -636,19 +636,19 @@ string_type to_sstring(unsigned long long value) {
 template <typename string_type = sstring>
 inline
 string_type to_sstring(float value) {
-    return to_sstring_sprintf<string_type>(value, "%f");
+    return to_sstring_sprintf<string_type>(value, "%g");
 }
 
 template <typename string_type = sstring>
 inline
 string_type to_sstring(double value) {
-    return to_sstring_sprintf<string_type>(value, "%f");
+    return to_sstring_sprintf<string_type>(value, "%g");
 }
 
 template <typename string_type = sstring>
 inline
 string_type to_sstring(long double value) {
-    return to_sstring_sprintf<string_type>(value, "%Lf");
+    return to_sstring_sprintf<string_type>(value, "%Lg");
 }
 
 template <typename string_type = sstring>
diff --git a/tests/httpd.cc b/tests/httpd.cc
index a7e4d1f15..911361983 100644
--- a/tests/httpd.cc
+++ b/tests/httpd.cc
@@ -78,7 +78,7 @@ SEASTAR_TEST_CASE(test_formatter)
     sstring str = "abc";
     BOOST_REQUIRE_EQUAL(json::formatter::to_json(str), "\"abc\"");
     float f = 1;
-    BOOST_REQUIRE_EQUAL(json::formatter::to_json(f), "1.000000");
+    BOOST_REQUIRE_EQUAL(json::formatter::to_json(f), "1");
     f = 1.0/0.0;
     BOOST_CHECK_THROW(json::formatter::to_json(f), std::out_of_range);
     f = -1.0/0.0;
@@ -86,7 +86,7 @@ SEASTAR_TEST_CASE(test_formatter)
     f = 0.0/0.0;
     BOOST_CHECK_THROW(json::formatter::to_json(f), std::invalid_argument);
     double d = -1;
-    BOOST_REQUIRE_EQUAL(json::formatter::to_json(d), "-1.000000");
+    BOOST_REQUIRE_EQUAL(json::formatter::to_json(d), "-1");
     d = 1.0/0.0;
     BOOST_CHECK_THROW(json::formatter::to_json(d), std::out_of_range);
     d = -1.0/0.0;