diff --git a/test/format-impl-test.cc b/test/format-impl-test.cc
index 3c944382..bf377699 100644
--- a/test/format-impl-test.cc
+++ b/test/format-impl-test.cc
@@ -277,7 +277,7 @@ TEST(FPTest, GetRoundDirection) {
   EXPECT_EQ(fmt::internal::up, get_round_direction(100, 51, 0));
   EXPECT_EQ(fmt::internal::down, get_round_direction(100, 40, 10));
   EXPECT_EQ(fmt::internal::up, get_round_direction(100, 60, 10));
-  for (int i = 41; i < 60; ++i)
+  for (size_t i = 41; i < 60; ++i)
     EXPECT_EQ(fmt::internal::unknown, get_round_direction(100, i, 10));
   uint64_t max = max_value<uint64_t>();
   EXPECT_THROW(get_round_direction(100, 100, 0), assertion_failure);
diff --git a/test/format-test.cc b/test/format-test.cc
index 2e1a0e70..fa5429f6 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1875,7 +1875,7 @@ TEST(FormatTest, Dynamic) {
 
   std::string result = fmt::vformat(
       "{} and {} and {}", fmt::basic_format_args<ctx>(
-                              args.data(), static_cast<unsigned>(args.size())));
+                              args.data(), static_cast<int>(args.size())));
 
   EXPECT_EQ("42 and abc1 and 1.5", result);
 }
@@ -2189,12 +2189,12 @@ TEST(FormatTest, WideFormatToN) {
 struct test_arg_id_handler {
   enum result { NONE, EMPTY, INDEX, NAME, ERROR };
   result res = NONE;
-  unsigned index = 0;
+  int index = 0;
   string_view name;
 
   FMT_CONSTEXPR void operator()() { res = EMPTY; }
 
-  FMT_CONSTEXPR void operator()(unsigned i) {
+  FMT_CONSTEXPR void operator()(int i) {
     res = INDEX;
     index = i;
   }
@@ -2230,9 +2230,9 @@ struct test_format_specs_handler {
 
   fmt::align_t align = fmt::align::none;
   char fill = 0;
-  unsigned width = 0;
+  int width = 0;
   fmt::internal::arg_ref<char> width_ref;
-  unsigned precision = 0;
+  int precision = 0;
   fmt::internal::arg_ref<char> precision_ref;
   char type = 0;
 
@@ -2258,14 +2258,14 @@ struct test_format_specs_handler {
   FMT_CONSTEXPR void on_hash() { res = HASH; }
   FMT_CONSTEXPR void on_zero() { res = ZERO; }
 
-  FMT_CONSTEXPR void on_width(unsigned w) { width = w; }
+  FMT_CONSTEXPR void on_width(int w) { width = w; }
   FMT_CONSTEXPR void on_dynamic_width(fmt::internal::auto_id) {}
-  FMT_CONSTEXPR void on_dynamic_width(unsigned index) { width_ref = index; }
+  FMT_CONSTEXPR void on_dynamic_width(int index) { width_ref = index; }
   FMT_CONSTEXPR void on_dynamic_width(string_view) {}
 
-  FMT_CONSTEXPR void on_precision(unsigned p) { precision = p; }
+  FMT_CONSTEXPR void on_precision(int p) { precision = p; }
   FMT_CONSTEXPR void on_dynamic_precision(fmt::internal::auto_id) {}
-  FMT_CONSTEXPR void on_dynamic_precision(unsigned index) {
+  FMT_CONSTEXPR void on_dynamic_precision(int index) {
     precision_ref = index;
   }
   FMT_CONSTEXPR void on_dynamic_precision(string_view) {}
@@ -2302,7 +2302,7 @@ TEST(FormatTest, ConstexprParseFormatSpecs) {
 struct test_parse_context {
   typedef char char_type;
 
-  FMT_CONSTEXPR unsigned next_arg_id() { return 11; }
+  FMT_CONSTEXPR int next_arg_id() { return 11; }
   template <typename Id> FMT_CONSTEXPR void check_arg_id(Id) {}
 
   FMT_CONSTEXPR const char* begin() { return nullptr; }
diff --git a/test/printf-test.cc b/test/printf-test.cc
index 2d68fab4..6fa2d476 100644
--- a/test/printf-test.cc
+++ b/test/printf-test.cc
@@ -5,12 +5,13 @@
 //
 // For the license information refer to format.h.
 
+#include "fmt/printf.h"
+
 #include <cctype>
 #include <climits>
 #include <cstring>
 
 #include "fmt/core.h"
-#include "fmt/printf.h"
 #include "gtest-extra.h"
 #include "util.h"
 
@@ -300,15 +301,15 @@ void TestLength(const char* length_spec, U value) {
   using fmt::internal::const_check;
   if (const_check(max <= static_cast<unsigned>(max_value<int>()))) {
     signed_value = static_cast<int>(value);
-    unsigned_value = static_cast<unsigned>(value);
+    unsigned_value = static_cast<unsigned long long>(value);
   } else if (const_check(max <= max_value<unsigned>())) {
     signed_value = static_cast<unsigned>(value);
-    unsigned_value = static_cast<unsigned>(value);
+    unsigned_value = static_cast<unsigned long long>(value);
   }
   if (sizeof(U) <= sizeof(int) && sizeof(int) < sizeof(T)) {
     signed_value = static_cast<long long>(value);
-    unsigned_value =
-        static_cast<typename std::make_unsigned<unsigned>::type>(value);
+    unsigned_value = static_cast<unsigned long long>(
+        static_cast<typename std::make_unsigned<unsigned>::type>(value));
   } else {
     signed_value = static_cast<typename make_signed<T>::type>(value);
     unsigned_value = static_cast<typename std::make_unsigned<T>::type>(value);
@@ -589,7 +590,7 @@ class custom_printf_arg_formatter : public formatter_t {
       if (round(value * pow(10, specs()->precision)) == 0.0) value = 0;
   return formatter_t::operator()(value);
 }
-};
+}
 
 typedef fmt::basic_format_args<context_t> format_args_t;
 
diff --git a/test/scan.h b/test/scan.h
index 50ac0941..af421bce 100644
--- a/test/scan.h
+++ b/test/scan.h
@@ -6,6 +6,8 @@
 // For the license information refer to format.h.
 
 #include <array>
+#include <cassert>
+#include <climits>
 
 #include "fmt/format.h"
 
@@ -135,21 +137,20 @@ struct scan_handler : error_handler {
       char c = *it++;
       if (c < '0' || c > '9') on_error("invalid input");
       // TODO: check overflow
-      value = value * 10 + (c - '0');
+      value = value * 10 + static_cast<unsigned>(c - '0');
     }
     scan_ctx_.advance_to(it);
     return value;
   }
 
   template <typename T = int> T read_int() {
-    T value = 0;
     auto it = scan_ctx_.begin(), end = scan_ctx_.end();
     bool negative = it != end && *it == '-';
     if (negative) ++it;
     scan_ctx_.advance_to(it);
-    value = read_uint<typename std::make_unsigned<T>::type>();
-    if (negative) value = -value;
-    return value;
+    const auto value = read_uint<typename std::make_unsigned<T>::type>();
+    if (negative) return -static_cast<T>(value);
+    return static_cast<T>(value);
   }
 
  public:
@@ -159,7 +160,7 @@ struct scan_handler : error_handler {
   const char* pos() const { return scan_ctx_.begin(); }
 
   void on_text(const char* begin, const char* end) {
-    auto size = end - begin;
+    auto size = to_unsigned(end - begin);
     auto it = scan_ctx_.begin();
     if (it + size > scan_ctx_.end() ||
         !std::equal(begin, end, make_checked(it, size))) {
@@ -197,7 +198,7 @@ struct scan_handler : error_handler {
     case scan_type::string_view_type: {
       auto s = it;
       while (it != end && *it != ' ') ++it;
-      *arg_.string_view = fmt::string_view(s, it - s);
+      *arg_.string_view = fmt::string_view(s, to_unsigned(it - s));
       scan_ctx_.advance_to(it);
       break;
     }