《你有什么打算》跟《你有什么计划》一样的吗？ 最近我对《打算》和《计划》有问题。如果我同事问我《这周末你有什么计划吗？》的话这有《你有什么打算吗？》的意思吗？如果不一样这两个句子有什么不同？

I am a little bit confused on when to use 计划 and when to use 打算. My understanding is that both mean "plan" but they seem to be entirely interchangeable. In what situations would I want to use one over the other?
they are same, 打算 often used in oral, 计划 is more formal.