diff --git a/include/fmt/format-inl.h b/include/fmt/format-inl.h
index 635a0c2a1b4f..c466362ae618 100644
--- a/include/fmt/format-inl.h
+++ b/include/fmt/format-inl.h
@@ -656,21 +656,21 @@ template <int GRISU_VERSION> struct grisu_shortest_handler {
       uint64_t d = integral ? diff : diff * data::POWERS_OF_10_64[-exp];
       while (remainder < d && error - remainder >= divisor &&
              (remainder + divisor < d ||
-              d - remainder > remainder + divisor - d)) {
+              d - remainder >= remainder + divisor - d)) {
         --buf[size - 1];
         remainder += divisor;
       }
       return digits::done;
     }
     uint64_t unit = integral ? 1 : data::POWERS_OF_10_64[-exp];
-    uint64_t up = diff + unit;  // wp_Wup
+    uint64_t up = (diff - 1) * unit;  // wp_Wup
     while (remainder < up && error - remainder >= divisor &&
            (remainder + divisor < up ||
-            up - remainder > remainder + divisor - up)) {
+            up - remainder >= remainder + divisor - up)) {
       --buf[size - 1];
       remainder += divisor;
     }
-    uint64_t down = diff - unit;  // wp_Wdown
+    uint64_t down = (diff + 1) * unit;  // wp_Wdown
     if (remainder < down && error - remainder >= divisor &&
         (remainder + divisor < down ||
          down - remainder > remainder + divisor - down)) {
@@ -684,7 +684,7 @@ template <int GRISU_VERSION> struct grisu_shortest_handler {
 
 template <typename Double, FMT_ENABLE_IF_T(sizeof(Double) == sizeof(uint64_t))>
 FMT_API bool grisu_format(Double value, buffer<char>& buf, int precision,
-                           unsigned options, int& exp) {
+                          unsigned options, int& exp) {
   FMT_ASSERT(value >= 0, "value is negative");
   bool fixed = (options & grisu_options::fixed) != 0;
   if (value <= 0) {  // <= instead of == to silence a warning.
diff --git a/include/fmt/format.h b/include/fmt/format.h
index 5df57ac6f064..1a566b8b7e05 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -2218,7 +2218,7 @@ class format_string_checker {
   FMT_CONSTEXPR void on_replacement_field(const Char*) {}
 
   FMT_CONSTEXPR const Char* on_format_specs(const Char* begin, const Char*) {
-    context_.advance_to(begin);
+    advance_to(context_, begin);
     return arg_id_ < NUM_ARGS ? parse_funcs_[arg_id_](context_) : begin;
   }
 
@@ -3226,6 +3226,12 @@ basic_format_context<Range, Char>::arg(basic_string_view<char_type> name) {
   return arg;
 }
 
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void advance_to(basic_parse_context<Char, ErrorHandler>& ctx,
+                              const Char* p) {
+  ctx.advance_to(ctx.begin() + (p - &*ctx.begin()));
+}
+
 template <typename ArgFormatter, typename Char, typename Context>
 struct format_handler : internal::error_handler {
   typedef typename ArgFormatter::range range;
@@ -3253,7 +3259,7 @@ struct format_handler : internal::error_handler {
   void on_arg_id(basic_string_view<Char> id) { arg = context.arg(id); }
 
   void on_replacement_field(const Char* p) {
-    parse_context.advance_to(p);
+    advance_to(parse_context, p);
     internal::custom_formatter<Context> f(parse_context, context);
     if (!visit_format_arg(f, arg))
       context.advance_to(
@@ -3261,7 +3267,7 @@ struct format_handler : internal::error_handler {
   }
 
   const Char* on_format_specs(const Char* begin, const Char* end) {
-    parse_context.advance_to(begin);
+    advance_to(parse_context, begin);
     internal::custom_formatter<Context> f(parse_context, context);
     if (visit_format_arg(f, arg)) return parse_context.begin();
     basic_format_specs<Char> specs;
@@ -3272,7 +3278,7 @@ struct format_handler : internal::error_handler {
         arg.type());
     begin = parse_format_specs(begin, end, handler);
     if (begin == end || *begin != '}') on_error("missing '}' in format string");
-    parse_context.advance_to(begin);
+    advance_to(parse_context, begin);
     context.advance_to(
         visit_format_arg(ArgFormatter(context, &parse_context, &specs), arg));
     return begin;
diff --git a/include/fmt/prepare.h b/include/fmt/prepare.h
index bfa7d8165529..6435fb77863d 100644
--- a/include/fmt/prepare.h
+++ b/include/fmt/prepare.h
@@ -310,7 +310,7 @@ class prepared_format {
       const format_part_t& part) const {
     const auto view = to_string_view(format_);
     const auto specification_begin = view.data() + part.end_of_argument_id;
-    parse_ctx.advance_to(specification_begin);
+    advance_to(parse_ctx, specification_begin);
   }
 
   template <typename Range, typename Context, typename Id>
diff --git a/include/fmt/ranges.h b/include/fmt/ranges.h
index 646d63f926b3..06fcaad53025 100644
--- a/include/fmt/ranges.h
+++ b/include/fmt/ranges.h
@@ -82,7 +82,7 @@ template <typename T> class is_like_std_string {
 
  public:
   static FMT_CONSTEXPR_DECL const bool value =
-      !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+      is_string<T>::value || !std::is_void<decltype(check<T>(FMT_NULL))>::value;
 };
 
 template <typename Char>