document.getElementById("myCheckBoxID").checked = true; // Check
document.getElementById("myCheckBoxID").checked = false;// Uncheck
// Check
document.getElementById("checkbox").checked = true;
// Uncheck
document.getElementById("checkbox").checked = false;<input type="checkbox" name="vehicle3" value="Boat" checked>
#If if helps you give it Thumbs up//HTML
<input type="checkbox" id="Numbers">Short Numbers</input>
<button type="button" onClick="changeCheckbox()">Save</button>
//JAVASCRIPT
function changeCheckbox(){
if(value)
document.getElementById("Numbers").checked = true;
}