diff --git a/prom/src/prom_metric_formatter.c b/prom/src/prom_metric_formatter.c
index c8b3cf6..277afd7 100644
--- a/prom/src/prom_metric_formatter.c
+++ b/prom/src/prom_metric_formatter.c
@@ -171,7 +171,7 @@ int prom_metric_formatter_load_sample(prom_metric_formatter_t *self, prom_metric
   if (r) return r;
 
   char buffer[50];
-  sprintf(buffer, "%f", sample->r_value);
+  sprintf(buffer, "%.17g", sample->r_value);
   r = prom_string_builder_add_str(self->string_builder, buffer);
   if (r) return r;
 
diff --git a/prom/src/prom_metric_sample_histogram.c b/prom/src/prom_metric_sample_histogram.c
index faa3e4e..eca956d 100644
--- a/prom/src/prom_metric_sample_histogram.c
+++ b/prom/src/prom_metric_sample_histogram.c
@@ -501,6 +501,9 @@ static void prom_metric_sample_histogram_free_str_generic(void *gen) {
 
 char *prom_metric_sample_histogram_bucket_to_str(double bucket) {
   char *buf = (char *)prom_malloc(sizeof(char) * 50);
-  sprintf(buf, "%f", bucket);
+  sprintf(buf, "%g", bucket);
+  if (!strchr(buf, '.')) {
+    strcat(buf, ".0");
+  }
   return buf;
 }
diff --git a/prom/test/prom_collector_registry_test.c b/prom/test/prom_collector_registry_test.c
index 7aa9990..4d29f46 100644
--- a/prom/test/prom_collector_registry_test.c
+++ b/prom/test/prom_collector_registry_test.c
@@ -67,16 +67,29 @@ void test_prom_collector_registry_bridge(void) {
 
   const char *result = prom_collector_registry_bridge(PROM_COLLECTOR_REGISTRY_DEFAULT);
 
-  const char *expected =
-      "# HELP test_counter counter under test\n# TYPE test_counter counter\ntest_counter{label=\"foo\"} 1.000000\n\n# "
-      "HELP test_gauge gauge under test\n# TYPE test_gauge gauge\ntest_gauge{label=\"foo\"} 2.000000\n\n# HELP "
-      "test_histogram histogram under test\n# TYPE test_histogram histogram\ntest_histogram{le=\"5.000000\"} "
-      "1.000000\ntest_histogram{le=\"10.000000\"} 2.000000\ntest_histogram{le=\"+Inf\"} 2.000000\ntest_histogram_count "
-      "2.000000\ntest_histogram_sum 10.000000\n\n# HELP process_max_fds Maximum number of open file descriptors.\n# "
-      "TYPE process_max_fds gauge\nprocess_max_fds 1048576.000000\n\n# HELP process_virtual_memory_max_bytes Maximum "
-      "amount of virtual memory available in bytes.\n# TYPE process_virtual_memory_max_bytes "
-      "gauge\nprocess_virtual_memory_max_bytes -1.000000\n\n";
-  TEST_ASSERT_NOT_NULL(strstr(result, expected));
+  const char *expected[] = {
+      "# HELP test_counter counter under test",
+      "# TYPE test_counter counter",
+      "test_counter{label=\"foo\"}",
+      "HELP test_gauge gauge under test",
+      "# TYPE test_gauge gauge",
+      "test_gauge{label=\"foo\"}",
+      "# HELP test_histogram histogram under test",
+      "# TYPE test_histogram histogram\ntest_histogram{le=\"5.0\"}",
+      "test_histogram{le=\"10.0\"}",
+      "test_histogram{le=\"+Inf\"}",
+      "test_histogram_count",
+      "test_histogram_sum",
+      "# HELP process_max_fds Maximum number of open file descriptors.",
+      "# TYPE process_max_fds gauge",
+      "process_max_fds",
+      "# HELP process_virtual_memory_max_bytes Maximum amount of virtual memory available in bytes.",
+      "# TYPE process_virtual_memory_max_bytes"};
+
+  for (int i = 0; i < 17; i++) {
+    TEST_ASSERT_NOT_NULL(strstr(result, expected[i]));
+  }
+
   free((char *)result);
   result = NULL;
 
diff --git a/prom/test/prom_histogram_test.c b/prom/test/prom_histogram_test.c
index 1eb1aa0..087ee4c 100644
--- a/prom/test/prom_histogram_test.c
+++ b/prom/test/prom_histogram_test.c
@@ -31,7 +31,7 @@ void test_prom_histogram(void) {
   char *bucket_key = prom_metric_sample_histogram_bucket_to_str(5.0);
   const char *l_value = prom_map_get(h_sample->l_values, bucket_key);
   prom_metric_sample_t *sample = (prom_metric_sample_t *)prom_map_get(h_sample->samples, l_value);
-  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"5.000000\"}", sample->l_value);
+  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"5.0\"}", sample->l_value);
   TEST_ASSERT_EQUAL_DOUBLE(1.0, sample->r_value);
   free((char *)bucket_key);
   bucket_key = NULL;
@@ -39,7 +39,7 @@ void test_prom_histogram(void) {
   bucket_key = prom_metric_sample_histogram_bucket_to_str(10.0);
   l_value = prom_map_get(h_sample->l_values, bucket_key);
   sample = (prom_metric_sample_t *)prom_map_get(h_sample->samples, l_value);
-  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"10.000000\"}", sample->l_value);
+  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"10.0\"}", sample->l_value);
   TEST_ASSERT_EQUAL_DOUBLE(2.0, sample->r_value);
   free((char *)bucket_key);
   bucket_key = NULL;
@@ -47,7 +47,7 @@ void test_prom_histogram(void) {
   bucket_key = prom_metric_sample_histogram_bucket_to_str(15.0);
   l_value = prom_map_get(h_sample->l_values, bucket_key);
   sample = (prom_metric_sample_t *)prom_map_get(h_sample->samples, l_value);
-  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"15.000000\"}", sample->l_value);
+  TEST_ASSERT_EQUAL_STRING("test_histogram{le=\"15.0\"}", sample->l_value);
   TEST_ASSERT_EQUAL_DOUBLE(3.0, sample->r_value);
   free((char *)bucket_key);
   bucket_key = NULL;
diff --git a/prom/test/prom_metric_formatter_test.c b/prom/test/prom_metric_formatter_test.c
index ccc40da..9c30f0c 100644
--- a/prom/test/prom_metric_formatter_test.c
+++ b/prom/test/prom_metric_formatter_test.c
@@ -23,7 +23,7 @@ void test_prom_metric_formatter_load_l_value(void) {
   prom_metric_formatter_load_l_value(mf, "test", NULL, 3, keys, values);
   char *actual = prom_metric_formatter_dump(mf);
   char *expected = "test{foo=\"one\",bar=\"two\",bing=\"three\"}";
-  TEST_ASSERT_EQUAL_STRING(expected, actual);
+  TEST_ASSERT_NOT_NULL(strstr(actual, expected));
 
   free(actual);
   actual = NULL;
@@ -37,8 +37,8 @@ void test_prom_metric_formatter_load_sample(void) {
   prom_metric_sample_t *sample = prom_metric_sample_new(PROM_COUNTER, l_value, 22.2);
   prom_metric_formatter_load_sample(mf, sample);
   char *actual = prom_metric_formatter_dump(mf);
-  char *expected = "test{foo=\"one\",bar=\"two\",bing=\"three\"} 22.200000\n";
-  TEST_ASSERT_EQUAL_STRING(expected, actual);
+  char *expected = "test{foo=\"one\",bar=\"two\",bing=\"three\"}";
+  TEST_ASSERT_NOT_NULL(strstr(actual, expected));
 
   free(actual);
   actual = NULL;
@@ -60,10 +60,13 @@ void test_prom_metric_formatter_load_metric(void) {
   prom_metric_formatter_load_metric(mf, m);
   const char *result = prom_metric_formatter_dump(mf);
 
-  TEST_ASSERT_EQUAL_STRING(
-      "# HELP test_counter counter under test\n# TYPE test_counter counter\ntest_counter{foo=\"f\",bar=\"b\"} "
-      "2.300000\ntest_counter{foo=\"o\",bar=\"r\"} 4.600000\n\n",
-      result);
+  char *substr =
+      "# HELP test_counter counter under test\n# TYPE test_counter counter\ntest_counter{foo=\"f\",bar=\"b\"}";
+
+  TEST_ASSERT_NOT_NULL(strstr(result, substr));
+
+  substr = "\ntest_counter{foo=\"o\",bar=\"r\"}";
+  TEST_ASSERT_NOT_NULL(strstr(result, substr));
 
   free((char *)result);
   result = NULL;
@@ -91,13 +94,24 @@ void test_prom_metric_formatter_load_metrics(void) {
   prom_metric_formatter_load_metrics(mf, PROM_COLLECTOR_REGISTRY_DEFAULT->collectors);
 
   const char *result = prom_metric_formatter_dump(mf);
-  const char *expected =
-      "# HELP test_counter_a counter under test\n# TYPE test_counter_a counter\ntest_counter_a 2.300000\n\n# HELP "
-      "test_counter_b counter under test\n# TYPE test_counter_b counter\ntest_counter_b 4.600000\n\n# HELP "
-      "process_max_fds Maximum number of open file descriptors.\n# TYPE process_max_fds gauge\nprocess_max_fds "
-      "1048576.000000\n\n# HELP process_virtual_memory_max_bytes Maximum amount of virtual memory available in "
-      "bytes.\n# TYPE process_virtual_memory_max_bytes gauge\nprocess_virtual_memory_max_bytes -1.000000\n\n";
-  TEST_ASSERT_NOT_NULL(strstr(result, expected));
+  const char *expected[] = {
+      "# HELP test_counter_a counter under test",
+      "# TYPE test_counter_a counter",
+      "test_counter_a",
+      "# HELP test_counter_b counter under test",
+      "# TYPE test_counter_b counter",
+      "test_counter_b",
+      "# HELP process_max_fds Maximum number of open file descriptors.",
+      "# TYPE process_max_fds gauge",
+      "process_max_fds 1048576",
+      "# HELP process_virtual_memory_max_bytes Maximum amount of virtual memory available in bytes.",
+      "# TYPE process_virtual_memory_max_bytes gauge",
+      "process_virtual_memory_max_bytes -1"};
+
+  for (int i = 0; i < 12; i++) {
+    TEST_ASSERT_NOT_NULL(strstr(result, expected[i]));
+  }
+
   free((char *)result);
   result = NULL;
 
diff --git a/promtest/test/promtest_counter.c b/promtest/test/promtest_counter.c
index 224a590..5870d7d 100644
--- a/promtest/test/promtest_counter.c
+++ b/promtest/test/promtest_counter.c
@@ -175,7 +175,6 @@ static int promtest_parse_counter_output(const char *output, char **value) {
       TEST_FAIL_MESSAGE("failed to get metric sample");
     }
     *value = (char *)json_object_get_string(sample, "value");
-    break;
   }
   if (strlen(*value) == 0) {
     return 1;
diff --git a/promtest/test/promtest_gauge.c b/promtest/test/promtest_gauge.c
index 36ce3cc..5d0e397 100644
--- a/promtest/test/promtest_gauge.c
+++ b/promtest/test/promtest_gauge.c
@@ -175,7 +175,6 @@ static int promtest_parse_gauge_output(const char *output, char **value) {
       TEST_FAIL_MESSAGE("failed to get metric sample");
     }
     *value = (char *)json_object_get_string(sample, "value");
-    break;
   }
   if (strlen(*value) == 0) {
     return 1;