For most travelers, including those from the US, UK, Australia, Canada, and many other countries, a visa is not required for short stays in Bali (Indonesia) of up to 30 days for tourism purposes. Upon arrival at the airport, you'll receive a visa exemption that allows you to stay for up to 30 days without applying for a visa in advance.
If you wish to stay longer than 30 days, you can apply for a visa extension or a visa on arrival that allows you to extend your stay for an additional 30 days.
For those traveling from countries that do not qualify for visa exemption or for longer stays, you might need to apply for a tourist visa at an Indonesian embassy or consulate in advance.
It's always a good idea to check the most up-to-date visa requirements for your nationality before traveling, as policies can change. You can visit the official Indonesian immigration website or consult with your travel agency for precise details.