The standard processing time of the Vietnam e-visa is 3 to 5 business days. Sometimes, it’s earlier than that, but there are also times that the processing will be delayed especially if you’re applying during the peak travel season.
The e-visa of Vietnam will let you stay in the country for a maximum of 30 days. It’s a single entry. If you plan to stay in Vietnam for more than 30 days, you are advised to choose visa on arrival for getting 3-month or 6-month visa.
If you already in Vietnam with an e-visa for 30 days and you want to stay more, see How To Get My E-visa Extended?