diff --git a/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.cpp b/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.cpp
index 34e2e8e9e7..6f51e894cd 100644
--- a/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.cpp
@@ -229,17 +229,18 @@ bool MathematicalValue::modulo_is_zero(Checked<i32> mod) const
         [](auto) -> bool { VERIFY_NOT_REACHED(); });
 }
 
-int MathematicalValue::logarithmic_floor() const
+ThrowCompletionOr<int> MathematicalValue::logarithmic_floor(VM& vm) const
 {
     return m_value.visit(
-        [](double value) {
+        [](double value) -> ThrowCompletionOr<int> {
             return static_cast<int>(floor(log10(value)));
         },
-        [](Crypto::SignedBigInteger const& value) {
+        [&](Crypto::SignedBigInteger const& value) -> ThrowCompletionOr<int> {
             // FIXME: Can we do this without string conversion?
-            return static_cast<int>(value.to_base_deprecated(10).length() - 1);
+            auto value_as_string = TRY_OR_THROW_OOM(vm, value.to_base(10));
+            return static_cast<int>(value_as_string.bytes_as_string_view().length() - 1);
         },
-        [](auto) -> int { VERIFY_NOT_REACHED(); });
+        [](auto) -> ThrowCompletionOr<int> { VERIFY_NOT_REACHED(); });
 }
 
 bool MathematicalValue::is_equal_to(MathematicalValue const& other) const
diff --git a/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.h b/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.h
index 2bb6e53501..e9d0ea131c 100644
--- a/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.h
+++ b/Userland/Libraries/LibJS/Runtime/Intl/MathematicalValue.h
@@ -79,7 +79,7 @@ public:
 
     bool modulo_is_zero(Checked<i32> mod) const;
 
-    int logarithmic_floor() const;
+    ThrowCompletionOr<int> logarithmic_floor(VM&) const;
 
     bool is_equal_to(MathematicalValue const&) const;
     bool is_less_than(MathematicalValue const&) const;
diff --git a/Userland/Libraries/LibJS/Runtime/Intl/NumberFormat.cpp b/Userland/Libraries/LibJS/Runtime/Intl/NumberFormat.cpp
index a8d5ba6348..a908ce55b8 100644
--- a/Userland/Libraries/LibJS/Runtime/Intl/NumberFormat.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Intl/NumberFormat.cpp
@@ -995,7 +995,7 @@ struct RawPrecisionResult {
 static ThrowCompletionOr<RawPrecisionResult> to_raw_precision_function(VM& vm, MathematicalValue const& number, int precision, PreferredResult mode)
 {
     RawPrecisionResult result {};
-    result.exponent = number.logarithmic_floor();
+    result.exponent = MUST_OR_THROW_OOM(number.logarithmic_floor(vm));
 
     if (number.is_number()) {
         result.number = number.divided_by_power(result.exponent - precision + 1);
@@ -1506,7 +1506,7 @@ ThrowCompletionOr<int> compute_exponent(VM& vm, NumberFormat& number_format, Mat
     }
 
     // 3. Let magnitude be the base 10 logarithm of x rounded down to the nearest integer.
-    int magnitude = number.logarithmic_floor();
+    int magnitude = MUST_OR_THROW_OOM(number.logarithmic_floor(vm));
 
     // 4. Let exponent be ComputeExponentForMagnitude(numberFormat, magnitude).
     int exponent = MUST_OR_THROW_OOM(compute_exponent_for_magnitude(vm, number_format, magnitude));
@@ -1524,7 +1524,7 @@ ThrowCompletionOr<int> compute_exponent(VM& vm, NumberFormat& number_format, Mat
     }
 
     // 8. Let newMagnitude be the base 10 logarithm of formatNumberResult.[[RoundedNumber]] rounded down to the nearest integer.
-    int new_magnitude = format_number_result.rounded_number.logarithmic_floor();
+    int new_magnitude = MUST_OR_THROW_OOM(format_number_result.rounded_number.logarithmic_floor(vm));
 
     // 9. If newMagnitude is magnitude - exponent, then
     if (new_magnitude == magnitude - exponent) {