diff --git a/index.html b/index.html
index cd44dc0..306ea5d 100644
--- a/index.html
+++ b/index.html
@@ -194,6 +194,7 @@ <h3>Running analysis....</h3>
                         <label for="alphaCheckbox"><input type="checkbox" id="alphaCheckbox" value="10"  onclick="GCODE.ui.processOptions()" > Render lines slightly transparent</label>
                         <!--<label for="widthModifier">Width modifier: <input type="text" value="2" id="widthModifier" onchange="GCODE.ui.processOptions()"/></label>-->
                         <label for="showNextLayer"><input type="checkbox" id="showNextLayer" value="9"  onclick="GCODE.ui.processOptions()" > Show +1 layer</label>
+                        <label for="showGrid"><input type="checkbox" id="showGrid" value="1"  onclick="GCODE.ui.processOptions()" checked> Show grid</label>
                     </div>
                 </div>
             </div>
@@ -230,6 +231,8 @@ <h3>Running analysis....</h3>
 						<label for="volumetricE"><input type="checkbox" id="volumetricE" onclick="GCODE.ui.processOptions()"> Volumetric E</label>
                         <label for="hourlyCost">Printer hourly cost: <input type="text" value="1.00" id="hourlyCost" onchange="GCODE.ui.processOptions()"/></label>
                         <label for="filamentPrice">Filament price(per gram): <input type="text" value="0.05" id="filamentPrice" onchange="GCODE.ui.processOptions()"/></label>
+                        <label for="bedSizeX">Bed size X <input type="text" value="200" id="bedSizeX" onchange="GCODE.ui.processOptions()"/></label> 
+                        <label for="bedSizeY">Bed size Y <input type="text" value="200" id="bedSizeY" onchange="GCODE.ui.processOptions()"/></label> 
                     </div>
                 </div>
             </div>
diff --git a/js/renderer.js b/js/renderer.js
index b22913b..8c72f81 100644
--- a/js/renderer.js
+++ b/js/renderer.js
@@ -11,7 +11,7 @@ GCODE.renderer = (function(){
     var canvas;
     var ctx;
     var zoomFactor= 3, zoomFactorDelta = 0.4;
-    var gridSizeX=200,gridSizeY=200,gridStep=10;
+    var gridStep=10;
     var ctxHeight, ctxWidth;
     var prevX=0, prevY=0;
 
@@ -41,11 +41,14 @@ GCODE.renderer = (function(){
         moveModel: true,
         differentiateColors: true,
         showNextLayer: false,
+        showGrid: true,
         alpha: false,
         actualWidth: false,
         renderErrors: false,
         renderAnalysis: false,
-        speedDisplayType: displayType.speed
+        speedDisplayType: displayType.speed,
+        bedSizeX: 500, 
+        bedSizeY: 500, 
     };
 
     var offsetModelX=0, offsetModelY=0;
@@ -218,6 +221,7 @@ GCODE.renderer = (function(){
     };
 
     var drawGrid = function() {
+        if (!renderOptions["showGrid"]) return;
         var i;
         ctx.strokeStyle = renderOptions["colorGrid"];
         ctx.lineWidth = 1;
@@ -228,16 +232,16 @@ GCODE.renderer = (function(){
         }
 
         ctx.beginPath();
-        for(i=0;i<=gridSizeX;i+=gridStep){
+        for(i=0;i<=renderOptions["bedSizeX"];i+=gridStep){
             ctx.moveTo(i*zoomFactor-offsetX, 0-offsetY);
-            ctx.lineTo(i*zoomFactor-offsetX, -gridSizeY*zoomFactor-offsetY);
+            ctx.lineTo(i*zoomFactor-offsetX, -renderOptions["bedSizeY"]*zoomFactor-offsetY);
         }
         ctx.stroke();
 
         ctx.beginPath();
-        for(i=0;i<=gridSizeY;i+=gridStep){
+        for(i=0;i<=renderOptions["bedSizeY"];i+=gridStep){
             ctx.moveTo(0-offsetX, -i*zoomFactor-offsetY);
-            ctx.lineTo(gridSizeX*zoomFactor-offsetX, -i*zoomFactor-offsetY);
+            ctx.lineTo(renderOptions["bedSizeX"]*zoomFactor-offsetX, -i*zoomFactor-offsetY);
         }
         ctx.stroke();
 
@@ -447,7 +451,7 @@ GCODE.renderer = (function(){
         init: function(){
             startCanvas();
             initialized = true;
-            ctx.translate((canvas.width - gridSizeX*zoomFactor)/2,gridSizeY*zoomFactor+(canvas.height - gridSizeY*zoomFactor)/2);
+            ctx.translate((canvas.width - renderOptions["bedSizeX"]*zoomFactor)/2,renderOptions["bedSizeY"]*zoomFactor+(canvas.height - renderOptions["bedSizeY"]*zoomFactor)/2);
         },
         setOption: function(options){
             for(var opt in options){
@@ -517,8 +521,8 @@ GCODE.renderer = (function(){
             min = mdlInfo.min;
 //            console.log(speeds);
 //            console.log(mdlInfo.min.x + ' ' + mdlInfo.modelSize.x);
-            offsetModelX = (gridSizeX/2-(mdlInfo.min.x+mdlInfo.modelSize.x/2))*zoomFactor;
-            offsetModelY = (mdlInfo.min.y+mdlInfo.modelSize.y/2)*zoomFactor-gridSizeY/2*zoomFactor;
+            offsetModelX = (renderOptions["bedSizeX"]/2-(mdlInfo.min.x+mdlInfo.modelSize.x/2))*zoomFactor;
+            offsetModelY = (mdlInfo.min.y+mdlInfo.modelSize.y/2)*zoomFactor-renderOptions["bedSizeY"]/2*zoomFactor;
             if(ctx)ctx.translate(offsetModelX, offsetModelY);
             var scaleF = mdlInfo.modelSize.x>mdlInfo.modelSize.y?(canvas.width)/mdlInfo.modelSize.x/zoomFactor:(canvas.height)/mdlInfo.modelSize.y/zoomFactor;
             var pt = ctx.transformedPoint(canvas.width/2,canvas.height/2);
diff --git a/js/ui.js b/js/ui.js
index 641521f..b5e356f 100644
--- a/js/ui.js
+++ b/js/ui.js
@@ -471,7 +471,6 @@ GCODE.ui = (function(){
 				nozzleDia: Number($('#nozzleDia').val()) || 0.4,
 				hourlyCost: Number($('#hourlyCost').val()) || 1.0,
 				filamentPrice: Number($('#filamentPrice').val()) || 0.05,
-
 				filamentType: document.getElementById('plasticABS').checked ? 'ABS' : 'PLA',
 			});
 
@@ -482,7 +481,11 @@ GCODE.ui = (function(){
 				differentiateColors: document.getElementById('differentiateColorsCheckbox').checked,
 				actualWidth: document.getElementById('thickExtrusionCheckbox').checked,
 				alpha: document.getElementById('alphaCheckbox').checked,
-				showNextLayer: document.getElementById('showNextLayer').checked,
+                showNextLayer: document.getElementById('showNextLayer').checked,
+                showGrid: document.getElementById('showGrid').checked,
+                
+				bedSizeX: Number($('#bedSizeX').val()) || 200,
+				bedSizeY: Number($('#bedSizeY').val()) || 200,
 			});
 
             showGCode = document.getElementById('showGCodeCheckbox').checked;