diff --git a/modules/juce_core/containers/juce_Variant.cpp b/modules/juce_core/containers/juce_Variant.cpp
index 05e6d929d3..1426f43f2d 100644
--- a/modules/juce_core/containers/juce_Variant.cpp
+++ b/modules/juce_core/containers/juce_Variant.cpp
@@ -175,7 +175,7 @@ public:
     int toInt (const ValueUnion& data) const noexcept override       { return (int) data.doubleValue; }
     int64 toInt64 (const ValueUnion& data) const noexcept override   { return (int64) data.doubleValue; }
     double toDouble (const ValueUnion& data) const noexcept override { return data.doubleValue; }
-    String toString (const ValueUnion& data) const override          { return String (data.doubleValue, 20); }
+    String toString (const ValueUnion& data) const override          { return minimiseLengthOfFloatString (String (data.doubleValue, 15, true)); }
     bool toBool (const ValueUnion& data) const noexcept override     { return data.doubleValue != 0.0; }
     bool isDouble() const noexcept override                          { return true; }
     bool isComparable() const noexcept override                      { return true; }
diff --git a/modules/juce_core/javascript/juce_JSON.h b/modules/juce_core/javascript/juce_JSON.h
index b7abed2e07..ff1588b9b3 100644
--- a/modules/juce_core/javascript/juce_JSON.h
+++ b/modules/juce_core/javascript/juce_JSON.h
@@ -110,13 +110,14 @@ public:
     /** Writes a JSON-formatted representation of the var object to the given stream.
         If allOnOneLine is true, the result will be compacted into a single line of text
         with no carriage-returns. If false, it will be laid-out in a more human-readable format.
-        The maximumDecimalPlaces parameter determines the precision of floating point numbers.
+        The maximumDecimalPlaces parameter determines the precision of floating point numbers
+        in scientific notation.
         @see toString
     */
     static void writeToStream (OutputStream& output,
                                const var& objectToFormat,
                                bool allOnOneLine = false,
-                               int maximumDecimalPlaces = 20);
+                               int maximumDecimalPlaces = 15);
 
     /** Returns a version of a string with any extended characters escaped. */
     static String escapeString (StringRef);
diff --git a/modules/juce_core/juce_core.cpp b/modules/juce_core/juce_core.cpp
index 72723c39ba..2e7c37c63d 100644
--- a/modules/juce_core/juce_core.cpp
+++ b/modules/juce_core/juce_core.cpp
@@ -125,7 +125,6 @@
 #include "containers/juce_PropertySet.cpp"
 #include "containers/juce_ReferenceCountedArray.cpp"
 #include "containers/juce_SparseSet.cpp"
-#include "containers/juce_Variant.cpp"
 #include "files/juce_DirectoryIterator.cpp"
 #include "files/juce_File.cpp"
 #include "files/juce_FileInputStream.cpp"
@@ -172,6 +171,7 @@
 #include "time/juce_RelativeTime.cpp"
 #include "time/juce_Time.cpp"
 #include "unit_tests/juce_UnitTest.cpp"
+#include "containers/juce_Variant.cpp"
 #include "javascript/juce_JSON.cpp"
 #include "javascript/juce_Javascript.cpp"
 #include "containers/juce_DynamicObject.cpp"
diff --git a/modules/juce_data_structures/values/juce_ValueTree.cpp b/modules/juce_data_structures/values/juce_ValueTree.cpp
index a4ffc0062a..8ff2983e9c 100644
--- a/modules/juce_data_structures/values/juce_ValueTree.cpp
+++ b/modules/juce_data_structures/values/juce_ValueTree.cpp
@@ -1157,32 +1157,63 @@ public:
 
     void runTest() override
     {
-        beginTest ("ValueTree");
-        auto r = getRandom();
-
-        for (int i = 10; --i >= 0;)
         {
-            MemoryOutputStream mo;
-            auto v1 = createRandomTree (nullptr, 0, r);
-            v1.writeToStream (mo);
+            beginTest ("ValueTree");
 
-            MemoryInputStream mi (mo.getData(), mo.getDataSize(), false);
-            auto v2 = ValueTree::readFromStream (mi);
-            expect (v1.isEquivalentTo (v2));
+            auto r = getRandom();
 
-            MemoryOutputStream zipped;
+            for (int i = 10; --i >= 0;)
             {
-                GZIPCompressorOutputStream zippedOut (zipped);
-                v1.writeToStream (zippedOut);
-            }
-            expect (v1.isEquivalentTo (ValueTree::readFromGZIPData (zipped.getData(), zipped.getDataSize())));
+                MemoryOutputStream mo;
+                auto v1 = createRandomTree (nullptr, 0, r);
+                v1.writeToStream (mo);
+
+                MemoryInputStream mi (mo.getData(), mo.getDataSize(), false);
+                auto v2 = ValueTree::readFromStream (mi);
+                expect (v1.isEquivalentTo (v2));
+
+                MemoryOutputStream zipped;
+                {
+                    GZIPCompressorOutputStream zippedOut (zipped);
+                    v1.writeToStream (zippedOut);
+                }
+                expect (v1.isEquivalentTo (ValueTree::readFromGZIPData (zipped.getData(), zipped.getDataSize())));
 
-            std::unique_ptr<XmlElement> xml1 (v1.createXml());
-            std::unique_ptr<XmlElement> xml2 (v2.createCopy().createXml());
-            expect (xml1->isEquivalentTo (xml2.get(), false));
+                std::unique_ptr<XmlElement> xml1 (v1.createXml());
+                std::unique_ptr<XmlElement> xml2 (v2.createCopy().createXml());
+                expect (xml1->isEquivalentTo (xml2.get(), false));
 
-            auto v4 = v2.createCopy();
-            expect (v1.isEquivalentTo (v4));
+                auto v4 = v2.createCopy();
+                expect (v1.isEquivalentTo (v4));
+            }
+        }
+
+        {
+            beginTest ("Float formatting");
+
+            ValueTree testVT ("Test");
+            Identifier number ("number");
+
+            std::map<double, String> tests;
+            tests[1] = "1";
+            tests[1.1] = "1.1";
+            tests[1.01] = "1.01";
+            tests[0.76378] = "7.6378e-1";
+            tests[-10] = "-1e1";
+            tests[10.01] = "1.001e1";
+            tests[0.0123] = "1.23e-2";
+            tests[-3.7e-27] = "-3.7e-27";
+            tests[1e+40] = "1e40";
+
+            for (auto& test : tests)
+            {
+                testVT.setProperty (number, test.first, nullptr);
+                auto lines = StringArray::fromLines (testVT.toXmlString());
+                lines.removeEmptyStrings();
+                auto numLines = lines.size();
+                expect (numLines > 1);
+                expectEquals (lines[numLines - 1], "<Test number=\"" + test.second + "\"/>");
+            }
         }
     }
 };