diff --git a/AK/Format.cpp b/AK/Format.cpp
index 0fe6f06a2b..e9c56489a7 100644
--- a/AK/Format.cpp
+++ b/AK/Format.cpp
@@ -390,7 +390,11 @@ void FormatBuilder::put_f64(
     StringBuilder string_builder;
     FormatBuilder format_builder { string_builder };
 
-    format_builder.put_i64(static_cast<i64>(value), base, false, upper_case, false, Align::Right, 0, ' ', sign_mode);
+    bool is_negative = value < 0.0;
+    if (is_negative)
+        value = -value;
+
+    format_builder.put_u64(static_cast<u64>(value), base, false, upper_case, false, Align::Right, 0, ' ', sign_mode, is_negative);
 
     if (precision > 0) {
         // FIXME: This is a terrible approximation but doing it properly would be a lot of work. If someone is up for that, a good
@@ -398,9 +402,6 @@ void FormatBuilder::put_f64(
         // https://youtu.be/4P_kbF0EbZM (Stephan T. Lavavej “Floating-Point <charconv>: Making Your Code 10x Faster With C++17's Final Boss”)
         value -= static_cast<i64>(value);
 
-        if (value < 0)
-            value = -value;
-
         double epsilon = 0.5;
         for (size_t i = 0; i < precision; ++i)
             epsilon /= 10.0;
diff --git a/AK/Tests/TestFormat.cpp b/AK/Tests/TestFormat.cpp
index 6ee5b8ed55..2a9a15762c 100644
--- a/AK/Tests/TestFormat.cpp
+++ b/AK/Tests/TestFormat.cpp
@@ -273,6 +273,12 @@ TEST_CASE(yay_this_implementation_sucks)
     EXPECT_EQ(String::formatted("{:.0}", .99999999999), "0");
 }
 
+TEST_CASE(magnitude_less_than_zero)
+{
+    EXPECT_EQ(String::formatted("{}", -0.654), "-0.654");
+    EXPECT_EQ(String::formatted("{}", 0.654), "0.654");
+}
+
 TEST_CASE(format_nullptr)
 {
     EXPECT_EQ(String::formatted("{}", nullptr), String::formatted("{:p}", static_cast<FlatPtr>(0)));