diff --git a/src/js/easymde.js b/src/js/easymde.js
index 8e73d6e..5eb37c8 100644
--- a/src/js/easymde.js
+++ b/src/js/easymde.js
@@ -1124,6 +1124,13 @@ function _toggleHeading(cm, direction, size) {
 
     var startPoint = cm.getCursor('start');
     var endPoint = cm.getCursor('end');
+    var sharpLevels = cm.options.backdrop.headingLevels || [],
+        minLevel = sharpLevels.length ? sharpLevels[0] : 1,
+        maxLevel = sharpLevels.length ? sharpLevels[sharpLevels.length-1] : 6;
+    if (size && sharpLevels.length && sharpLevels.indexOf(size) === -1) {
+        cm.focus();
+        return false;
+    }
     for (var i = startPoint.line; i <= endPoint.line; i++) {
         (function (i) {
             var text = cm.getLine(i);
@@ -1132,14 +1139,20 @@ function _toggleHeading(cm, direction, size) {
             if (direction !== undefined) {
                 if (currHeadingLevel <= 0) {
                     if (direction == 'bigger') {
-                        text = '###### ' + text;
+                        text = '#'.repeat(maxLevel) + ' ' + text;
                     } else {
-                        text = '# ' + text;
+                        text = '#'.repeat(minLevel) + ' ' + text;
+                    }
+                } else if (currHeadingLevel == maxLevel && direction == 'smaller') {
+                    text = text.substr(maxLevel + 1);
+                } else if (currHeadingLevel == minLevel && direction == 'bigger') {
+                    text = text.substr(minLevel + 1);
+                } else if (sharpLevels.length) {
+                    if (direction == 'bigger') {
+                        text = '#'.repeat(sharpLevels[sharpLevels.indexOf(currHeadingLevel)-1]) + text.replace(/^[#]+/, '' );
+                    } else {
+                        text = '#'.repeat(sharpLevels[sharpLevels.indexOf(currHeadingLevel)+1]) + text.replace(/^[#]+/, '' );
                     }
-                } else if (currHeadingLevel == 6 && direction == 'smaller') {
-                    text = text.substr(7);
-                } else if (currHeadingLevel == 1 && direction == 'bigger') {
-                    text = text.substr(2);
                 } else {
                     if (direction == 'bigger') {
                         text = text.substr(1);
@@ -2205,108 +2218,138 @@ EasyMDE.prototype.render = function (el) {
     }
     if (options.parsingConfig.headingLevels) {
         // If the *headingLevels* argument is present, set our custom modifiers
-        var makeBiggerHeadline = function(headline, from, to) {
-            headline = headline || '';
-            if (!from || !to) {
+        var headingMakeBigger = function(heading, from, to) {
+            heading = heading || '';
+            if (!from || !to || from >= to) {
                 return '';
             }
             var level = '';
-            while (from < to) {
-                level += '#';
-                from++;
+            if (!heading.length) {
+                while (from < to) {
+                    level += '#';
+                    from++;
+                }
+                level += ' ';
+                return level;
+            } else {
+                while (to > 0) {
+                    level += '#';
+                    to--;
+                }
+                level += ' ';
+                return /#/.test(heading) ? heading.replace(/^[#]+\s*/, level) : level;
             }
-            level += ' ';
-            return /#/.test(headline) ? headline.replace(/#\s*/, level) : level;
         };
-        var headlineNeedUpdate = function(myCurrHeadline, allowedHeadlingLevels, levelSearchDir) {
-            if (!myCurrHeadline || !allowedHeadlingLevels) {
+        var headingMakeSmaller = function(heading, from, to) {
+            heading = heading || '';
+            if (!from || !to || from <= to) {
+                return '';
+            }
+            var level = '';
+            if (!heading.length) {
+                while (from > to) {
+                    level += '#';
+                    from--;
+                }
+                level += ' ';
+                return level;
+            } else {
+                while (to > 0) {
+                    level += '#';
+                    to--;
+                }
+                level += ' ';
+                return /#/.test(heading) ? heading.replace(/^[#]+\s*/, level) : level;
+            }
+        };
+        var headingNeedUpdate = function(currHeading, allowedHeadingLevels, levelSearchDir) {
+            if (!currHeading || !allowedHeadingLevels) {
                 return false;
             }
-            myCurrHeadline = myCurrHeadline.trim();
-            if (!/^#+/.test(myCurrHeadline)){
+            currHeading = currHeading.trim();
+            if (!/^#+/.test(currHeading)){
                 return false;
             }
-            var currHeadlingLevel = (myCurrHeadline.match(/^([#]+)/g) || [''])[0].length;
-            if (allowedHeadlingLevels.indexOf(currHeadlingLevel) !== -1) {
+            var currHeadingLevel = (currHeading.match(/^([#]+)/g) || [''])[0].length;
+            if (allowedHeadingLevels.indexOf(currHeadingLevel) !== -1) {
                 return false;
             }
             levelSearchDir = levelSearchDir || 'asc';
             var newHeadingLevel = -1, n = 0;
             if (levelSearchDir === 'asc') {
-                while (n < allowedHeadlingLevels.length) {
-                    if (allowedHeadlingLevels[n] > currHeadlingLevel) {
-                        newHeadingLevel = allowedHeadlingLevels[n];
+                while (n < allowedHeadingLevels.length) {
+                    if (allowedHeadingLevels[n] > currHeadingLevel) {
+                        newHeadingLevel = allowedHeadingLevels[n];
                         break;
                     }
                     n++;
                 }
             }
             if (newHeadingLevel < 0) {
-                n = allowedHeadlingLevels.length - 1;
+                n = allowedHeadingLevels.length - 1;
                 while (n > -1) {
-                    if (allowedHeadlingLevels[n] < currHeadlingLevel) {
-                        newHeadingLevel = allowedHeadlingLevels[n];
+                    if (allowedHeadingLevels[n] < currHeadingLevel) {
+                        newHeadingLevel = allowedHeadingLevels[n];
                         break;
                     }
                     n--;
                 }
                 if (levelSearchDir === 'dsc') {
-                    currHeadlingLevel += 1;
+                    currHeadingLevel += 1;
                     if (newHeadingLevel < 0) {
                         newHeadingLevel = 0;
                     }
                 }
             }
-            if (newHeadingLevel < 0 || newHeadingLevel === currHeadlingLevel) {
+            if (newHeadingLevel < 0 || newHeadingLevel === currHeadingLevel) {
                 return false;
             }
             return {
-                from: currHeadlingLevel,
+                from: currHeadingLevel,
                 to: newHeadingLevel,
-                diff: Math.abs(newHeadingLevel - currHeadlingLevel),
+                diff: Math.abs(newHeadingLevel - currHeadingLevel),
             };
         };
-        var checkNewHeadline = function(cm, obj) {
-            var myHeadline = cm.getRange({
+        var headingCheckNew = function(cm, obj) {
+            var currHeading = cm.getRange({
                 line: obj.from.line,
                 ch: 0,
             }, {
                 line: obj.to.line,
                 ch: obj.to.ch,
             });
-            var levels = headlineNeedUpdate(myHeadline, cm.options.backdrop.headingLevels);
-            if (!levels || !levels.from || !levels.to) {
+            var myLevels = headingNeedUpdate(currHeading, cm.options.backdrop.headingLevels);
+            if (!myLevels || !myLevels.from || !myLevels.to) {
                 return false;
             }
             if (obj.from.line === obj.to.line) {
                 // Most simple case when a modification has occured on a single line
-                if (levels.to > levels.from) {
+                if (myLevels.to > myLevels.from) {
                     // Current level is forbidden so we jump to the closest upper level allowed
                     // We only need to reset the sharp numbers with the appropriate value before the modification is applied
-                    obj.text[0] = makeBiggerHeadline('', levels.from, levels.to);
-                }
-                else {
+                    obj.text[0] = headingMakeBigger('', myLevels.from, myLevels.to);
+                } else {
                     // The current level is forbidden and we jump to the closest lower level available
                     // A bit more is needed: we have to cancel the requested update and trigger a replacement with the existing sharp signs
                     obj.cancel();
-                    var newHeadline = '';
-                    while (levels.to > 0) {
-                        newHeadline += '#';
-                        levels.to--;
+                    var newHeading = '';
+                    while (myLevels.to > 0) {
+                        newHeading += '#';
+                        myLevels.to--;
                     }
-                    newHeadline += ' ';
-                    cm.doc.replaceRange(newHeadline, {
+                    newHeading += ' ';
+                    cm.doc.replaceRange(newHeading, {
                         line: obj.from.line,
                         ch: 0,
                     }, {
                         line: obj.to.line,
                         ch: obj.to.ch,
-                    }, myHeadline ); // 4th arguments to keep a trace in the history when possible
+                    }, currHeading ); // 4th arguments to keep a trace in the history when possible
                 }
             }
             return true;
         };
-        var checkExistingHeadline = function(cm, obj) {
+        var headingCheckExisting = function(cm, obj) {
             var myChar = cm.getRange({
                 line: obj.from.line,
                 ch: obj.from.ch,
@@ -2314,9 +2357,8 @@ EasyMDE.prototype.render = function (el) {
                 line: obj.to.line,
                 ch: obj.to.ch + 1,
             });
-            // console.log( '==' + myChar + '==' );
             if (!/\s|#/.test(myChar || '')) {
-                // Don't bother to go further if no headlines were detected
+                // Don't bother to go further if no headling were detected
                 return false;
             }
             if ((obj.from.line === obj.to.line) && obj.text.length === 1) {
@@ -2327,12 +2369,11 @@ EasyMDE.prototype.render = function (el) {
                         return false;
                     }
                     if (!/#/.test(myText)) {
-                        myText = '# ' + myText.trim(); // Wasn't headline
-                    }
-                    else {
+                        myText = '# ' + myText.trim(); // Wasn't heading
+                    } else {
                         myText = myText.replace(/#/, '##'); // Increment one sharp sign
-                    };
-                    myLevels = headlineNeedUpdate(myText, cm.options.backdrop.headingLevels);
+                    }
+                    myLevels = headingNeedUpdate(myText, cm.options.backdrop.headingLevels);
                     if (!myLevels) {
                         return false;
                     }
@@ -2348,7 +2389,7 @@ EasyMDE.prototype.render = function (el) {
                     return true;
                 }
                 else if (/delete/.test(obj.origin) && obj.text[0] === '') {
-                    myLevels = headlineNeedUpdate(myText.replace(/#/, ''), cm.options.backdrop.headingLevels, 'dsc');
+                    myLevels = headingNeedUpdate(myText.replace(/#/, ''), cm.options.backdrop.headingLevels, 'dsc');
                     if (!myLevels) {
                         return false;
                     }
@@ -2378,50 +2419,95 @@ EasyMDE.prototype.render = function (el) {
                 }
             }
         };
+        var headingCheckRow = function(row, cm) {
+            if (!row || !/^#/.test(row.trim())) {
+                return row;
+            }
+            row = row.replace(/^(\s*)#/, '#');
+            var myLevels = headingNeedUpdate(row, cm.options.backdrop.headingLevels);
+            if (!myLevels || !myLevels.from || !myLevels.to) {
+                return row;
+            } else if (myLevels.from < myLevels.to) {
+                return headingMakeBigger(row, myLevels.from, myLevels.to);
+            } else if (myLevels.to < myLevels.from) {
+                return headingMakeSmaller(row, myLevels.from, myLevels.to);
+            }
+            return row;
+        };
         this.codemirror.on('beforeChange', function (cm, obj) {
-            console.log(obj);
-            if (!obj || !obj.from || !obj.to || !obj.text) {
+            // console.log(obj);
+            if (!obj || !obj.from || !obj.to || !obj.text || !obj.text.length) {
                 // Don't go further 'cause a required argument is missing...
                 return false;
             }
-            if ((obj.from.line === obj.to.line) ) {
+            if ((obj.from.line === obj.to.line) && obj.text.length < 2) {
                 if (obj.to.ch > 6) {
                     // No need to trigger a check if we are on the same line at character 7 or upper
-                    // As we are sure the cursor is not inside a range containing a sharp sign
+                    // As we are sure the cursor was not inside a range containing a sharp sign
                     return false;
                 }
-                if (obj.from.ch === 0 && obj.to.ch === 0 && /\s|\b/.test(obj.text[0] || '')) {
-                    // Prevent space at the beginning of the line
+                if (obj.from.ch === 0 && obj.to.ch === 0 && /\s/.test(obj.text[0] || '')) {
+                    // (Force) Prevent space at the beginning of the line
                     obj.cancel();
                     return false;
                 }
             }
-            if (!obj.text.length) {
-                // Just in case
-                return false;
-            }
             if (!obj.origin) {
-                // Just in case
+                // If a modification was triggered by a code and not an human
+                // The origin can be "undefined", so just in case set one.
                 obj.origin = '+none';
             }
             if (/input/.test(obj.origin)) { // Something was added
                 if (obj.text.length === 1 && obj.text[0].length === 1) {
                     // Only one character on one line is being updated
                     if (obj.text[0] === ' ') {
-                        return checkNewHeadline(cm, obj);
-                    }
-                    else if (obj.text[0] === '#') {
-                        return checkExistingHeadline(cm, obj);
-                    }
-                    else {
-                        return false;
+                        return headingCheckNew(cm, obj);
+                    } else if (obj.text[0] === '#') {
+                        return headingCheckExisting(cm, obj);
                     }
                 }
             }
             else if (/delete/.test(obj.origin)) { // Something was removed
                 if (obj.text.length === 1 && !obj.text[0].length) {
                     // Only one character on one line has been removed
-                    return checkExistingHeadline(cm, obj);
+                    return headingCheckExisting(cm, obj);
+                }
+            }
+            if (obj.text.length < 2) {
+                return false;
+            }
+            // Multilines modification like a paste
+            var r;
+            if (obj.from.ch === 0) {
+                // Loop each row and check for headers
+                for (r=0; r<obj.text.length; r++) {
+                    obj.text[r] = headingCheckRow(obj.text[r], cm);
+                }
+            }
+            else if (obj.from.ch > 7) {
+                // We are sure an existing header is not involved
+                // So exclude the first row from the loop
+                for (r=1; r<obj.text.length; r++) {
+                    obj.text[r] = headingCheckRow(obj.text[r], cm);
+                }
+            }
+            else {
+                // We need to check the first row in case an existing header is involved
+                var startText, oldText, newText;
+                for (r=0; r<obj.text.length; r++) {
+                    if (!r) { // First row
+                        startText = cm.getRange({line: obj.from.line, ch: 0}, {line: obj.from.line, ch: obj.from.ch});
+                        if (/#/.test(startText)) {
+                            oldText = startText + obj.text[r];
+                            newText = headingCheckRow(oldText, cm);
+                            if (oldText !== newText) { // A modification has been made
+                                obj.text[r] = newText;
+                                obj.from.ch = 0;
+                            }
+                        }
+                    } else { // 2nd and next rows
+                        obj.text[r] = headingCheckRow(obj.text[r], cm);
+                    }
                 }
             }
         });