The current challenging situation of COVID 19 is being mitigated by offering free vaccine to the population. There has been a lot of negative press in regard to the usefulness and the side effects of the various COVID 19 vaccines, as well as some positive feedback. CoVacSenti is a sentiment analysis system which will explore the sentiments of the British population about the COVID 19 vaccines provided in UK. The data will be obtained from Twitter and the main programming language used will be Python.