diff --git a/include/fast_float/decimal_to_binary.h b/include/fast_float/decimal_to_binary.h
index b9b96f4..a7ee289 100644
--- a/include/fast_float/decimal_to_binary.h
+++ b/include/fast_float/decimal_to_binary.h
@@ -98,7 +98,9 @@ compute_error(int64_t q, uint64_t w) noexcept {
 // packed. However, in some very rare cases, the computation will fail. In such
 // cases, we return an adjusted_mantissa with a negative power of 2: the caller
 // should recompute in such cases.
-template <typename binary>
+// known_in_range: the caller knows that q is within the range of powers of
+// ten, so only w == 0 is checked.
+template <typename binary, bool known_in_range = false>
 fastfloat_really_inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
 compute_float(int64_t q, uint64_t w) noexcept {
   adjusted_mantissa answer;
@@ -107,7 +109,7 @@ compute_float(int64_t q, uint64_t w) noexcept {
   bool const q_out_of_range = uint64_t(q - binary::smallest_power_of_ten()) >
                               uint64_t(binary::largest_power_of_ten() -
                                        binary::smallest_power_of_ten());
-  if ((w == 0) || q_out_of_range) {
+  if ((w == 0) || (!known_in_range && q_out_of_range)) {
     bool const underflow = (w == 0) | (q < binary::smallest_power_of_ten());
     answer.power2 = int32_t(!underflow) * binary::infinite_power();
     answer.mantissa = 0;
diff --git a/include/fast_float/parse_number.h b/include/fast_float/parse_number.h
index d3856cb..0db46ec 100644
--- a/include/fast_float/parse_number.h
+++ b/include/fast_float/parse_number.h
@@ -445,8 +445,20 @@ from_chars_float_advanced(UC const *first, UC const *last, T &value,
     return answer;
   }
 
+#ifdef __clang__
+  // If the exponent passed Clinger's range test, it is well within range. GCC
+  // carries this into compute_float by itself; clang needs the instantiation
+  // without the range check. The mantissa can still be zero when the rounding
+  // mode is not to nearest.
+  adjusted_mantissa am =
+      (binary_format<T>::min_exponent_fast_path() <= pns.exponent &&
+       pns.exponent <= binary_format<T>::max_exponent_fast_path())
+          ? compute_float<binary_format<T>, true>(pns.exponent, pns.mantissa)
+          : compute_float<binary_format<T>>(pns.exponent, pns.mantissa);
+#else
   adjusted_mantissa am =
       compute_float<binary_format<T>>(pns.exponent, pns.mantissa);
+#endif
   // Slow path B (rare): Eisel-Lemire could not resolve; digit_comp needs the
   // integer/fraction spans. Route to the cold helper (clinger there is a
   // dead-effect since it already failed here; the cold re-parse + digit_comp