diff --git a/calibration.html b/calibration.html
index 16e637f..e32be60 100644
--- a/calibration.html
+++ b/calibration.html
@@ -115,7 +115,7 @@
         <pre>M500</pre>
         <p>For the bed, <b>PIDTEMPBED</b> must be enabled in the firmware, then the command is quite similar:</p>
         <pre>M303 E-1 S60 U1</pre>
-        <p>The bed is selected with <ib>E-1</b>, and the temp set to 60 degrees. Substiture as necessary for your normal printing bed temperature. Once again save to EEPROM afterwards with:</p>
+        <p>The bed is selected with <ib>E-1</b>, and the temp set to 60 degrees. Substitute as necessary for your normal printing bed temperature. Once again save to EEPROM afterwards with:</p>
         <pre>M500</pre>
         <p>It may be preferable to have the printer as close to printing conditions as possible during these tuning prodecures. That means having filament loaded and the part cooling fan on for PLA temperatures.</p>
     </div>