 <p>For future reference,</p> <p>You should be using a WebService (ASMX) file to process and return your JSON. Remember that the javascript success block will only be called with a returned http 200 status code.</p> <p>If you ever get to using the MVC framework its even easier by just returning a JSON result type.</p> <p>If you wanted to keep the aspx hack, you can call the following to remove the HTML</p> <pre><code>response.clear(); response.write(yourJSON); response.end(); </code></pre> <p>But again i would discourage from doing this and recommend the dedicated service.</p>