diff --git a/poi/src/main/java/org/apache/poi/ss/formula/atp/AnalysisToolPak.java b/poi/src/main/java/org/apache/poi/ss/formula/atp/AnalysisToolPak.java
index bf92661089..0824942f37 100644
--- a/poi/src/main/java/org/apache/poi/ss/formula/atp/AnalysisToolPak.java
+++ b/poi/src/main/java/org/apache/poi/ss/formula/atp/AnalysisToolPak.java
@@ -175,6 +175,8 @@ public final class AnalysisToolPak implements UDFFinder {
         r(m, "SERIESSUM", null);
         r(m, "SINGLE", Single.instance);
         r(m, "SQRTPI", Sqrtpi.instance);
+        r(m, "STDEV.S", Stdevs.instance);
+        r(m, "STDEV.P", Stdevp.instance);
         r(m, "SUMIFS", Sumifs.instance);
         r(m, "SWITCH", Switch.instance);
         r(m, "TBILLEQ", null);
@@ -195,6 +197,8 @@ public final class AnalysisToolPak implements UDFFinder {
         r(m, "YIELD", null);
         r(m, "YIELDDISC", null);
         r(m, "YIELDMAT", null);
+        r(m, "VAR.S", Vars.instance);
+        r(m, "VAR.P", Varp.instance);
 
         return m;
     }
diff --git a/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevp.java b/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevp.java
new file mode 100644
index 0000000000..765ea02cb2
--- /dev/null
+++ b/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevp.java
@@ -0,0 +1,16 @@
+package org.apache.poi.ss.formula.atp;
+
+import org.apache.poi.ss.formula.OperationEvaluationContext;
+import org.apache.poi.ss.formula.eval.ValueEval;
+import org.apache.poi.ss.formula.functions.AggregateFunction;
+import org.apache.poi.ss.formula.functions.FreeRefFunction;
+
+public class Stdevp implements FreeRefFunction {
+
+    public static final Stdevp instance = new Stdevp();
+
+    @Override
+    public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) {
+        return AggregateFunction.STDEVP.evaluate(args, ec.getRowIndex(), ec.getColumnIndex());
+    }
+}
diff --git a/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevs.java b/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevs.java
new file mode 100644
index 0000000000..f2beab15d9
--- /dev/null
+++ b/poi/src/main/java/org/apache/poi/ss/formula/atp/Stdevs.java
@@ -0,0 +1,16 @@
+package org.apache.poi.ss.formula.atp;
+
+import org.apache.poi.ss.formula.OperationEvaluationContext;
+import org.apache.poi.ss.formula.eval.ValueEval;
+import org.apache.poi.ss.formula.functions.AggregateFunction;
+import org.apache.poi.ss.formula.functions.FreeRefFunction;
+
+public class Stdevs implements FreeRefFunction {
+
+    public static final Stdevs instance = new Stdevs();
+
+    @Override
+    public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) {
+        return AggregateFunction.STDEV.evaluate(args, ec.getRowIndex(), ec.getColumnIndex());
+    }
+}
diff --git a/poi/src/main/java/org/apache/poi/ss/formula/atp/Varp.java b/poi/src/main/java/org/apache/poi/ss/formula/atp/Varp.java
new file mode 100644
index 0000000000..84133665e3
--- /dev/null
+++ b/poi/src/main/java/org/apache/poi/ss/formula/atp/Varp.java
@@ -0,0 +1,16 @@
+package org.apache.poi.ss.formula.atp;
+
+import org.apache.poi.ss.formula.OperationEvaluationContext;
+import org.apache.poi.ss.formula.eval.ValueEval;
+import org.apache.poi.ss.formula.functions.AggregateFunction;
+import org.apache.poi.ss.formula.functions.FreeRefFunction;
+
+public class Varp implements FreeRefFunction {
+
+    public static final Varp instance = new Varp();
+
+    @Override
+    public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) {
+        return AggregateFunction.VARP.evaluate(args, ec.getRowIndex(), ec.getColumnIndex());
+    }
+}
diff --git a/poi/src/main/java/org/apache/poi/ss/formula/atp/Vars.java b/poi/src/main/java/org/apache/poi/ss/formula/atp/Vars.java
new file mode 100644
index 0000000000..18c4f16273
--- /dev/null
+++ b/poi/src/main/java/org/apache/poi/ss/formula/atp/Vars.java
@@ -0,0 +1,16 @@
+package org.apache.poi.ss.formula.atp;
+
+import org.apache.poi.ss.formula.OperationEvaluationContext;
+import org.apache.poi.ss.formula.eval.ValueEval;
+import org.apache.poi.ss.formula.functions.AggregateFunction;
+import org.apache.poi.ss.formula.functions.FreeRefFunction;
+
+public class Vars implements FreeRefFunction {
+
+    public static final Vars instance = new Vars();
+
+    @Override
+    public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) {
+        return AggregateFunction.VAR.evaluate(args, ec.getRowIndex(), ec.getColumnIndex());
+    }
+}
diff --git a/poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdevp.java b/poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdev.java
similarity index 83%
rename from poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdevp.java
rename to poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdev.java
index 15ea474bfa..2397ad99fe 100644
--- a/poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdevp.java
+++ b/poi/src/test/java/org/apache/poi/ss/formula/functions/TestStdev.java
@@ -29,18 +29,22 @@ import static org.apache.poi.ss.util.Utils.addRow;
 import static org.apache.poi.ss.util.Utils.assertDouble;
 
 /**
- * Testcase for function STDEVP()
+ * Testcase for functions: STDEV(), STDEVP(), STDEV.S(), STDEV.P()
  */
-public class TestStdevp {
+public class TestStdev {
 
     //https://support.microsoft.com/en-us/office/stdevp-function-1f7c1c88-1bec-4422-8242-e9f7dc8bb195
+    //https://support.microsoft.com/en-us/office/stdev-p-function-6e917c05-31a0-496f-ade7-4f4e7462f285
+    //https://support.microsoft.com/en-us/office/stdev-s-function-7d69cf97-0c1f-4acf-be27-f3e83904cc23
     @Test
     void testMicrosoftExample1() throws IOException {
         try (HSSFWorkbook wb = initWorkbook1()) {
             HSSFFormulaEvaluator fe = new HSSFFormulaEvaluator(wb);
             HSSFCell cell = wb.getSheetAt(0).getRow(0).createCell(12);
             assertDouble(fe, cell, "STDEVP(A3:A12)", 26.0545581424825, 0.00000000001);
+            assertDouble(fe, cell, "STDEV.P(A3:A12)", 26.0545581424825, 0.00000000001);
             assertDouble(fe, cell, "STDEV(A3:A12)", 27.4639157198435, 0.00000000001);
+            assertDouble(fe, cell, "STDEV.S(A3:A12)", 27.4639157198435, 0.00000000001);
         }
     }
 
diff --git a/poi/src/test/java/org/apache/poi/ss/formula/functions/TestVar.java b/poi/src/test/java/org/apache/poi/ss/formula/functions/TestVar.java
new file mode 100644
index 0000000000..e569a2e468
--- /dev/null
+++ b/poi/src/test/java/org/apache/poi/ss/formula/functions/TestVar.java
@@ -0,0 +1,67 @@
+
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+package org.apache.poi.ss.formula.functions;
+
+import org.apache.poi.hssf.usermodel.HSSFCell;
+import org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator;
+import org.apache.poi.hssf.usermodel.HSSFSheet;
+import org.apache.poi.hssf.usermodel.HSSFWorkbook;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+
+import static org.apache.poi.ss.util.Utils.addRow;
+import static org.apache.poi.ss.util.Utils.assertDouble;
+
+/**
+ * Testcase for functions: VAR.S(), VAR.P()
+ */
+public class TestVar {
+
+    //https://support.microsoft.com/en-us/office/var-s-function-913633de-136b-449d-813e-65a00b2b990b
+    //https://support.microsoft.com/en-us/office/var-p-function-73d1285c-108c-4843-ba5d-a51f90656f3a
+    @Test
+    void testMicrosoftExample1() throws IOException {
+        try (HSSFWorkbook wb = initWorkbook1()) {
+            HSSFFormulaEvaluator fe = new HSSFFormulaEvaluator(wb);
+            HSSFCell cell = wb.getSheetAt(0).getRow(0).createCell(12);
+            assertDouble(fe, cell, "VARP(A3:A12)", 678.84, 0.00000000001);
+            assertDouble(fe, cell, "VAR.P(A3:A12)", 678.84, 0.00000000001);
+            assertDouble(fe, cell, "VAR(A3:A12)", 754.27, 0.005);
+            assertDouble(fe, cell, "VAR.S(A3:A12)", 754.27, 0.005);
+        }
+    }
+
+    private HSSFWorkbook initWorkbook1() {
+        HSSFWorkbook wb = new HSSFWorkbook();
+        HSSFSheet sheet = wb.createSheet();
+        addRow(sheet, 0, "Data");
+        addRow(sheet, 1, "Strength");
+        addRow(sheet, 2, 1345);
+        addRow(sheet, 3, 1301);
+        addRow(sheet, 4, 1368);
+        addRow(sheet, 5, 1322);
+        addRow(sheet, 6, 1310);
+        addRow(sheet, 7, 1370);
+        addRow(sheet, 8, 1318);
+        addRow(sheet, 9, 1350);
+        addRow(sheet, 10, 1303);
+        addRow(sheet, 11, 1299);
+        return wb;
+    }
+}