diff --git a/Exception/InvalidMARCspecException.php b/Exception/InvalidMARCspecException.php
index 569602a..1598a1c 100755
--- a/Exception/InvalidMARCspecException.php
+++ b/Exception/InvalidMARCspecException.php
@@ -44,7 +44,7 @@ class InvalidMARCspecException extends \UnexpectedValueException {
     const LENGTHIND    = 'For indicators only two characters at are allowed.';
     const INDCHAR1     = 'At minimum one indicator must be a digit or a lowercase alphabetic character.';
     const INDCHAR2     = 'For indicators only digits, lowercase alphabetic characters and "_" are allowed.';
-    const NEGATIVE     = 'Ending character position or index must be equal or higher than starting character potion or index.';
+    const NEGATIVE     = 'Ending character or index position must be equal or higher than starting character or index position.';
     const PR1          = 'Assuming index or character position or range. Minimum one character is required. None given.';
     const PR2          = 'Assuming index or character position or range. Only digits, the character # and one "-" is allowed.';
     const PR3          = 'Assuming index or character range. At least two digits or the character # must be present.';
diff --git a/Field.php b/Field.php
index f1c0608..a0b2ca8 100755
--- a/Field.php
+++ b/Field.php
@@ -425,6 +425,11 @@ public function jsonSerialize()
             $_fieldSpec['indexEnd'] = $indexEnd;
         }
         
+        if(($indexLength = $this->getIndexLength()) !== null)
+        {
+            $_fieldSpec['indexLength'] = $indexLength;
+        }
+        
         if(($charStart = $this->getCharStart()) !== null)
         {
             $_fieldSpec['charStart'] = $charStart;
@@ -549,6 +554,8 @@ public function offsetExists($offset)
             break;
             case 'indexEnd': return isset($this->indexEnd);
             break;
+            case 'indexLength': return !is_null($this->getIndexLength());
+            break;
             case 'charStart': return isset($this->charStart);
             break;
             case 'charEnd': return isset($this->charEnd);
@@ -583,6 +590,8 @@ public function offsetGet($offset)
             break;
             case 'indexEnd': return $this->getIndexEnd();
             break;
+            case 'indexLength': return $this->getIndexLength();
+            break;
             case 'charStart': return $this->getCharStart();
             break;
             case 'charEnd': return $this->getCharEnd();
@@ -613,6 +622,7 @@ public function offsetSet($offset,$value)
         {
             case 'indexStart': $this->setIndexStartEnd($value);
             break;
+            
             case 'indexEnd':
                 if(!isset($this['indexStart']))
                 {
@@ -623,8 +633,13 @@ public function offsetSet($offset,$value)
                     $this->setIndexStartEnd($this['indexStart'],$value);
                 }
             break;
+            
+            case 'indexLength': throw new \UnexpectedValueException("indexLength is always calculated.");
+            break;
+            
             case 'charStart': $this->setCharStartEnd($value);
             break;
+            
             case 'charEnd':
                 if(!isset($this['charStart']))
                 {
@@ -635,14 +650,19 @@ public function offsetSet($offset,$value)
                     $this->setCharStartEnd($this['charStart'],$value);
                 }
             break;
+            
             case 'charLength': throw new \UnexpectedValueException("CharLength is always calculated.");
             break;
+            
             case 'indicator1': $this->setIndicator1($value);
             break;
+            
             case 'indicator2': $this->setIndicator2($value);
             break;
+            
             case 'subSpecs': $this->addSubSpec($value);
             break;
+            
             default: throw new \UnexpectedValueException("Offset $offset cannot be set.");
         }
     }
diff --git a/PositionOrRange.php b/PositionOrRange.php
index c7ad3df..a30a594 100755
--- a/PositionOrRange.php
+++ b/PositionOrRange.php
@@ -122,6 +122,46 @@ public function getCharLength()
         }
     }
     
+    /**
+     * {@inheritdoc}
+     */
+    public function getIndexLength()
+    {
+        if( is_null($this->getIndexStart()) && is_null($this->getIndexEnd()) )
+        {
+            return null;
+        }
+        if( !is_null($this->getIndexStart()) && is_null($this->getIndexEnd()) )
+        {
+            return 1;
+        }
+        // both defined
+        if($this->indexStart === $this->indexEnd) 
+        {
+            return 1;
+        }
+        if('#' === $this->indexStart && '#' !== $this->indexEnd)
+        {
+            return $this->indexEnd + 1;
+        }
+        if('#' !== $this->indexStart && '#' === $this->indexEnd)
+        {
+            return null;
+        }
+        else
+        {
+            $length = $this->indexEnd - $this->indexStart + 1;
+            if(1 > $length)
+            {
+                throw new InvalidMARCspecException(
+                    InvalidMARCspecException::PR.
+                    InvalidMARCspecException::NEGATIVE
+                );
+            }
+            return $length;
+        }
+    }
+    
     /**
      * {@inheritdoc}
      */
@@ -157,7 +197,7 @@ protected function validatePos($pos)
         
         for($x = 0; $x < $posLength; $x++)
         {
-            if(!preg_match('/[0-9-#]/', $pos[$x])) // alphabetic characters etc. are not valid
+            if(!preg_match('/[0-9\-#]/', $pos[$x])) // alphabetic characters etc. are not valid
             {
                 throw new InvalidMARCspecException(
                     InvalidMARCspecException::PR.
diff --git a/PositionOrRangeInterface.php b/PositionOrRangeInterface.php
index feea1ac..05dd735 100755
--- a/PositionOrRangeInterface.php
+++ b/PositionOrRangeInterface.php
@@ -133,4 +133,18 @@ public function getCharEnd();
     * @throws \InvalidArgumentException if length is less than 1
     */
     public function getCharLength();
+    
+    /**
+    *
+    * Get length of index range
+    *
+    * @api
+    * 
+    * @access public
+    * 
+    * @return null|int $length The index range length
+    * 
+    * @throws \InvalidArgumentException if length is less than 1
+    */
+    public function getIndexLength();
 } // EOI
diff --git a/README.md b/README.md
index dc6c216..856c3f1 100755
--- a/README.md
+++ b/README.md
@@ -6,9 +6,9 @@ For currently supported version of **MARCspec - A common MARC record path langua
 
 # Installation
 
-Installation can be done by using [composer](https://getcomposer.org/doc/00-intro.md) 
+Installation can be done by using [composer](https://getcomposer.org/doc/00-intro.md).
 
-```php
+```json
 {
     "require": {
         "ck/php-marcspec": "1.*"
diff --git a/Subfield.php b/Subfield.php
index 224c649..8b29b53 100755
--- a/Subfield.php
+++ b/Subfield.php
@@ -278,6 +278,11 @@ public function jsonSerialize()
             $_subfieldSpec['indexEnd'] = $indexEnd;
         }
         
+        if(($indexLength = $this->getIndexLength()) !== null)
+        {
+            $_subfieldSpec['indexLength'] = $indexLength;
+        }
+        
         if(($charStart = $this->getCharStart()) !== null) 
         {
             $_subfieldSpec['charStart'] = $charStart;
@@ -384,26 +389,21 @@ public function offsetExists($offset)
         {
             
             case 'tag': return isset($this->tag);
-                break;
-            
+            break;
             case 'indexStart': return isset($this->indexStart);
-                break;
-            
+            break;
             case 'indexEnd': return isset($this->indexEnd);
-                break;
-            
+            break;
+            case 'indexLength': return !is_null($this->getIndexLength());
+            break;
             case 'charStart': return isset($this->charStart);
-                break;
-            
+            break;
             case 'charEnd': return isset($this->charEnd);
-                break;
-                
+            break;
             case 'charLength': return !is_null($this->getCharLength());
-                break;
-            
+            break;
             case 'subSpecs': return (0 < count($this->subSpecs)) ? true : false;
-                break;
-            
+            break;
             default: return false;
         }
     }
@@ -420,26 +420,21 @@ public function offsetGet($offset)
         switch($offset)
         {
             case 'tag': return $this->getTag();
-                break;
-            
+            break;
             case 'indexStart': return $this->getIndexStart();
-                break;
-            
+            break;
             case 'indexEnd': return $this->getIndexEnd();
-                break;
-            
+            break;
+            case 'indexLength': return $this->getIndexLength();
+            break;
             case 'charStart': return $this->getCharStart();
-                break;
-            
+            break;
             case 'charEnd': return $this->getCharEnd();
-                break;
-            
+            break;
             case 'charLength': return $this->getCharLength();
-                break;
-            
+            break;
             case 'subSpecs': return $this->getSubSpecs();
-                break;
-            
+            break;
             default: return null;
         }
     }
@@ -456,39 +451,42 @@ public function offsetSet($offset,$value)
         switch($offset)
         {
             case 'indexStart': $this->setIndexStartEnd($value);
-                break;
+            break;
             
             case 'indexEnd':
-                if(!isset($this['indexStart']))
-                {
-                    $this->setIndexStartEnd($value,$value);
-                }
-                else
-                {
-                    $this->setIndexStartEnd($this['indexStart'],$value);
-                }
-                break;
+            if(!isset($this['indexStart']))
+            {
+                $this->setIndexStartEnd($value,$value);
+            }
+            else
+            {
+                $this->setIndexStartEnd($this['indexStart'],$value);
+            }
+            break;
             
-            case 'charStart': $this->setCharStartEnd($value);
-                break;
+            case 'indexLength': throw new \UnexpectedValueException("indexLength is always calculated.");
+            break;
             
+            case 'charStart': $this->setCharStartEnd($value);
+            break;
+
             case 'charEnd':
-                if(!isset($this['charStart']))
-                {
-                    $this->setCharStartEnd($value,$value);
-                }
-                else
-                {
-                    $this->setCharStartEnd($this['charStart'],$value);
-                }
-                break;
-            
+            if(!isset($this['charStart']))
+            {
+                $this->setCharStartEnd($value,$value);
+            }
+            else
+            {
+                $this->setCharStartEnd($this['charStart'],$value);
+            }
+            break;
+
             case 'charLength': throw new \UnexpectedValueException("CharLength is always calculated.");
-                break;
-            
+            break;
+
             case 'subSpecs': $this->addSubSpec($value);
-                break;
-            
+            break;
+
             default: throw new \UnexpectedValueException("Offset $offset cannot be set.");
         }
     }
diff --git a/Test/FieldTest.php b/Test/FieldTest.php
index ca00899..c641af5 100755
--- a/Test/FieldTest.php
+++ b/Test/FieldTest.php
@@ -234,11 +234,11 @@ public function testValidFieldSpec1()
             
             $fieldSpec = $this->fieldspec('245[1-3]');
             $this->assertSame(1, $fieldSpec->getIndexStart());
-            $this->assertSame(3, $fieldSpec->getIndexEnd());            
+            $this->assertSame(3, $fieldSpec->getIndexEnd());
             
             $fieldSpec = $this->fieldspec('245[1-#]');
             $this->assertSame(1, $fieldSpec->getIndexStart());
-            $this->assertSame('#', $fieldSpec->getIndexEnd());            
+            $this->assertSame('#', $fieldSpec->getIndexEnd());
             
             $fieldSpec = $this->fieldspec('245[#-3]');
             $this->assertSame('#', $fieldSpec->getIndexStart());
@@ -320,7 +320,7 @@ public function testValidFieldSpec23()
     /**
      * test character position and range
      */
-    public function testSetAndGet()
+    public function testSetAndGetChar()
     {
             $fieldSpec = $this->fieldspec('LDR');
             $fieldSpec->setCharStartEnd(0,3);
@@ -349,8 +349,40 @@ public function testSetAndGet()
             $this->assertSame("#", $fieldSpec->getCharStart());
             $this->assertSame(3, $fieldSpec->getCharEnd());
             $this->assertSame(4, $fieldSpec->getCharLength());
+    }
+    
+    /**
+     * test index position and range
+     */
+    public function testSetAndGetIndex()
+    {
+            $fieldSpec = $this->fieldspec('300');
+            $fieldSpec->setIndexStartEnd(0,3);
+            $this->assertSame('300', $fieldSpec->getTag());
+            $this->assertSame(0, $fieldSpec->getIndexStart());
+            $this->assertSame(3, $fieldSpec->getIndexEnd());
+            $this->assertSame(4, $fieldSpec->getIndexLength());
             
-
+            $fieldSpec = $this->fieldspec('300');
+            $fieldSpec->setIndexStartEnd("#",3);
+            $this->assertSame('300', $fieldSpec->getTag());
+            $this->assertSame("#", $fieldSpec->getIndexStart());
+            $this->assertSame(3, $fieldSpec->getIndexEnd());
+            $this->assertSame(4, $fieldSpec->getIndexLength());
+            
+            $fieldSpec = $this->fieldspec('300');
+            $fieldSpec->setIndexStartEnd(0,4);
+            $this->assertSame('300', $fieldSpec->getTag());
+            $this->assertSame(0, $fieldSpec->getIndexStart());
+            $this->assertSame(4, $fieldSpec->getIndexEnd());
+            $this->assertSame(5, $fieldSpec->getIndexLength());
+                        
+            $fieldSpec = $this->fieldspec('300');
+            $fieldSpec->setIndexStartLength("#",4);
+            $this->assertSame('300', $fieldSpec->getTag());
+            $this->assertSame("#", $fieldSpec->getIndexStart());
+            $this->assertSame(3, $fieldSpec->getIndexEnd());
+            $this->assertSame(4, $fieldSpec->getIndexLength());
     }
     
     /**
diff --git a/Test/SubfieldTest.php b/Test/SubfieldTest.php
index 4bc5bbb..985c5ae 100755
--- a/Test/SubfieldTest.php
+++ b/Test/SubfieldTest.php
@@ -255,7 +255,7 @@ public function testValidSubfieldSpec22()
     /**
      * test character position and range
      */
-    public function testSetAndGet()
+    public function testSetAndGetChar()
     {
             $Subfield = $this->subfieldspec('$a');
             $Subfield->setCharStartEnd('0','3');
@@ -284,10 +284,41 @@ public function testSetAndGet()
             $this->assertSame("#", $Subfield->getCharStart());
             $this->assertSame(3, $Subfield->getCharEnd());
             $this->assertSame(4, $Subfield->getCharLength());
-            
+    }
 
+    /**
+     * test index position and range
+     */
+    public function testSetAndGetIndex()
+    {
+        $Subfield = $this->subfieldspec('$a');
+        $Subfield->setIndexStartEnd('0','3');
+        $this->assertSame('a', $Subfield->getTag());
+        $this->assertSame(0, $Subfield->getIndexStart());
+        $this->assertSame(3, $Subfield->getIndexEnd());
+        $this->assertSame(4, $Subfield->getIndexLength());
+        
+        $Subfield = $this->subfieldspec('$a');
+        $Subfield->setIndexStartEnd("#",3);
+        $this->assertSame('a', $Subfield->getTag());
+        $this->assertSame("#", $Subfield->getIndexStart());
+        $this->assertSame(3, $Subfield->getIndexEnd());
+        $this->assertSame(4, $Subfield->getIndexLength());
+        
+        $Subfield = $this->subfieldspec('$a');
+        $Subfield->setIndexStartEnd(0,4);
+        $this->assertSame('a', $Subfield->getTag());
+        $this->assertSame(0, $Subfield->getIndexStart());
+        $this->assertSame(4, $Subfield->getIndexEnd());
+        $this->assertSame(5, $Subfield->getIndexLength());
+        
+        $Subfield = $this->subfieldspec('$a');
+        $Subfield->setIndexStartLength("#",4);
+        $this->assertSame('a', $Subfield->getTag());
+        $this->assertSame("#", $Subfield->getIndexStart());
+        $this->assertSame(3, $Subfield->getIndexEnd());
+        $this->assertSame(4, $Subfield->getIndexLength());
     }
-    
     /**
      * test encoding
      */