Google Flights
You can find cheap flight deals to anywhere in the world on Google Flights. Just enter your departure city, choose Anywhere as the destination, and select Explore.
You can pick specific dates or leave departure and return dates blank if your plans are flexible. The cheapest fares to popular destinations will appear.
You can filter the results to see only nonstop flights or flights under a certain price to more easily plan your perfect budget trip.
If you already have a destination in mind, you can turn on price tracking to get alerts if the fare changes for a route or flight.