diff --git a/lib/node-progress.js b/lib/node-progress.js
index 8eb0740..b06a484 100644
--- a/lib/node-progress.js
+++ b/lib/node-progress.js
@@ -69,6 +69,7 @@ function ProgressBar(fmt, options) {
   this.lastRender = -Infinity;
   this.callback = options.callback || function () {};
   this.tokens = {};
+  this.spaceRequiredForTokens = 0;
   this.lastDraw = '';
 }
 
@@ -147,8 +148,22 @@ ProgressBar.prototype.render = function (tokens, force) {
     .replace(':percent', percent.toFixed(0) + '%')
     .replace(':rate', Math.round(rate));
 
+  /* account for the replacement of the extra tokens */
+  var spaceRequiredForTokens = 0;
+  if (this.tokens) for (var key in this.tokens) {
+    if(str.indexOf(":"+key) == -1) continue;
+    spaceRequiredForTokens += this.tokens[key].length - (key.length+1)
+  };
+
+  /* ensure spaceRequiredForTokens is at least 0, and is consistent accross ticks */
+  if(spaceRequiredForTokens > this.spaceRequiredForTokens) {
+    this.spaceRequiredForTokens = spaceRequiredForTokens;
+  } else {
+    spaceRequiredForTokens = this.spaceRequiredForTokens;
+  }
+
   /* compute the available space (non-zero) for the bar */
-  var availableSpace = Math.max(0, this.stream.columns - str.replace(':bar', '').length);
+  var availableSpace = Math.max(0, this.stream.columns - spaceRequiredForTokens - str.replace(':bar', '').length);
   if(availableSpace && process.platform === 'win32'){
     availableSpace = availableSpace - 1;
   }