The level one is to "exercise normal precautions", level two would be "exercise increased caution", level three is "reconsider travel", and level four would be "do not travel", a top American diplomat said.
"We'll simplify our messages to US citizens, replacing emergency and security messages with just alerts in an easy to-understand format," Carl C Risch, Assistant Secretary of State for Consular Affairs said.
A standard format would help US citizens find and use important security information more easily, he said adding that content would be optimised for mobile users and readily sharable on social media.
As per the new procedures beginning in January, countries would be designated in various level from one to four depending on the threat perception.
In some cases, various parts of a single country might have different levels of travel advisories, he said.
Bringing in this new system is part of the effort to simplify the travel alerts. The process for this was started in the previous Obama administration.
"We want them to be not confusing, and that people know how to react to the information that is being provided by the government. There is no desire to cause fear or paranoia where it's not justified for some reason," he said.
"Level one is exercise normal precautions. This is the lowest level for safety and security risk. So there's some risk to any international travel, of course, but the conditions in other countries may differ from those in the United States, and may change at any time," he said.
"Level two, would be be aware of heightened risks to safety and security," he said adding the state department provides additional advice for travellers in these areas.
"Conditions in any country may change, again, at any time," Mr Risch said.
Level three is about avoiding travel due to serious risks of safety and security.
"Level four - the 'do not travel' - is the highest advisory level due to life-threatening risks," Mr Risch said adding that "during an emergency, the US government may have very limited ability to provide assistance, so leave as soon as it is safe to do so," he said.