CRM Web-to-lead hidden Checkbox Fields

CRM Web-to-lead hidden Checkbox Fields

Need a little help setting a checkbox to true via a hidden web to lead form field.  Anyone have this working?  We have the field in question enabled in webtolead. We've tried the following to no avail:

<input type="hidden" name="checkbox" value="true">
<input type="hidden" name="checkbox" value="1">
<input type="hidden" name="checkbox" value="yes">