diff --git a/src/libxrpl/protocol/STNumber.cpp b/src/libxrpl/protocol/STNumber.cpp
index 3c5336405b..5944d4cd6b 100644
--- a/src/libxrpl/protocol/STNumber.cpp
+++ b/src/libxrpl/protocol/STNumber.cpp
@@ -263,36 +263,44 @@ numberFromJson(SField const& field, json::Value const& value)
     auto const negative = num.mantissa() < 0;
     auto mantissa = Number::externalToInternal(num.mantissa());
     auto exponent = num.exponent();
-    XRPL_ASSERT(negative == parts.negative, "numberFromJson : signs agree");
+
+    // Number zero has a special representation, so if the result is 0, nothing else needs to match.
+    // i.e. the Json string could be negative 0 ("-0") or a very "large" 0 ("0e99"), but they all
+    // represent 0.
+    bool const isZero = num == beast::kZero && parts.mantissa == 0;
+    XRPL_ASSERT(negative == parts.negative || isZero, "numberFromJson : signs agree");
     static_assert(
         // NOLINTNEXTLINE(misc-redundant-expression)
         std::is_same_v<decltype(mantissa), decltype(parts.mantissa)>);
     static_assert(
         // NOLINTNEXTLINE(misc-redundant-expression)
         std::is_same_v<decltype(exponent), decltype(parts.exponent)>);
-    auto const minMantissa = Number::minMantissa();
-    while (parts.exponent > exponent && parts.mantissa < minMantissa)
+    if (!isZero)
     {
-        parts.mantissa *= 10;
-        --parts.exponent;
-    }
-    while (parts.exponent < exponent && mantissa < minMantissa)
-    {
-        // This should only happen in the edge case where the internal mantissa > kMaxRep
-        mantissa *= 10;
-        --exponent;
-    }
-    while (parts.exponent < exponent && parts.mantissa % 10 == 0)
-    {
-        // LCOV_EXCL_START
-        // This will probably never be needed
-        parts.mantissa /= 10;
-        ++parts.exponent;
-        // LCOV_EXCL_STOP
-    }
+        auto constexpr minMantissa = Number::kMaxRep / 10;
+        while (parts.exponent > exponent && parts.mantissa < minMantissa)
+        {
+            parts.mantissa *= 10;
+            --parts.exponent;
+        }
+        while (parts.exponent < exponent && mantissa < minMantissa)
+        {
+            // This should only happen in the edge case where the internal mantissa > kMaxRep
+            mantissa *= 10;
+            --exponent;
+        }
+        while (parts.exponent < exponent && parts.mantissa % 10 == 0)
+        {
+            // LCOV_EXCL_START
+            // This will probably never be needed
+            parts.mantissa /= 10;
+            ++parts.exponent;
+            // LCOV_EXCL_STOP
+        }
 
-    if (negative != parts.negative || mantissa != parts.mantissa || exponent != parts.exponent)
-        Throw<std::runtime_error>("number can not be represented");
+        if (negative != parts.negative || mantissa != parts.mantissa || exponent != parts.exponent)
+            Throw<std::runtime_error>("number can not be represented");
+    }
 
     return STNumber{field, num};
 }
diff --git a/src/test/protocol/STNumber_test.cpp b/src/test/protocol/STNumber_test.cpp
index 5c9c3fd83c..7339df7c04 100644
--- a/src/test/protocol/STNumber_test.cpp
+++ b/src/test/protocol/STNumber_test.cpp
@@ -108,23 +108,43 @@ struct STNumber_test : public beast::unit_test::Suite
                 auto const minInt = std::to_string(std::numeric_limits<std::int64_t>::min());
                 if (Number::getMantissaScale() == MantissaRange::MantissaScale::Small)
                 {
-                    BEAST_EXPECT(
-                        numberFromJson(sfNumber, maxInt) ==
-                        STNumber(sfNumber, Number{9'223'372'036'854'775, 3}));
-                    BEAST_EXPECT(
-                        numberFromJson(sfNumber, minInt) ==
-                        STNumber(sfNumber, Number{-9'223'372'036'854'775, 3}));
+                    // min/maxInt can't be exactly represented with the small mantissa, so they
+                    // don't parse, and are expected to throw.
+                    try
+                    {
+                        auto const bad = numberFromJson(sfNumber, maxInt);
+                        fail();
+                    }
+                    catch (std::exception const& e)
+                    {
+                        BEAST_EXPECT(std::string(e.what()) == "number can not be represented");
+                    }
+                    try
+                    {
+                        auto const bad = numberFromJson(sfNumber, minInt);
+                        fail();
+                    }
+                    catch (std::exception const& e)
+                    {
+                        BEAST_EXPECT(std::string(e.what()) == "number can not be represented");
+                    }
                 }
                 else
                 {
+                    // with large mantissas, maxint is fine
                     BEAST_EXPECT(
                         numberFromJson(sfNumber, maxInt) ==
                         STNumber(sfNumber, Number{9'223'372'036'854'775'807, 0}));
-                    BEAST_EXPECT(
-                        numberFromJson(sfNumber, minInt) ==
-                        STNumber(
-                            sfNumber,
-                            Number{true, 9'223'372'036'854'775'808ULL, 0, Number::Normalized{}}));
+                    // but minint's mantissa is > kMaxRep, and so rounds, and thus can't be parsed
+                    try
+                    {
+                        auto const bad = numberFromJson(sfNumber, minInt);
+                        fail();
+                    }
+                    catch (std::exception const& e)
+                    {
+                        BEAST_EXPECT(std::string(e.what()) == "number can not be represented");
+                    }
                 }
             }