First, decide why you need a certificate. For many goals a confident level is enough without any exam — the document is needed only when an embassy, a university or an employer explicitly asks for it. If there is such a requirement, the choice depends on the country and the goal: the formats differ in score scale, validity and the range of organisations that recognise them.
IELTS is the most universal option for visas, admission and work in the UK, Canada, Australia, Ireland and many other countries; the result is usually valid for two years.
TOEFL has traditionally been aimed at universities in the US and Canada.
FCE (B2 First) by Cambridge confirms a stable B2 level and is issued for life — handy when you need a lasting proof of your English.
BEC was the Cambridge business line; outside mainland China its role is now played by Linguaskill Business.
We prepare for exams in lessons tailored to your goal: first a level check, then work on the task format, timing and common traps. A simple first step — take the online level test to see your starting point.