have something at your/their etc fingertipsKNOW somethingto have knowledge or information ready and available to use very easily 手头有某物〔可供随时使用〕,对某物了如指掌 We have all the facts and figures at our fingertips. 我们手头掌握所有的详细资料。
→ have something at your/their etc fingertips at fingertip(1)