See COVID-19 vaccine efficacy and effectiveness in The Lancet:
Vaccine efficacy is generally reported as a relative risk reduction—ie, the ratio of attack rates [i.e. any symptomatic infection] with and without a vaccine.
Ranking by reported efficacy gives relative risk reductions of 95% for the Pfizer–BioNTech, 94% for the Moderna–NIH, 90% for the Gamaleya, 67% for the J&J, and 67% for the AstraZeneca–Oxford vaccines. However, RRR should be seen against the background risk of being infected and becoming ill with COVID-19, which varies between populations and over time.
The good news is that the vaccines (particularly mRNA vaccines) are also very effective at preventing severe disease conditional on any symptoms, and reasonably effective at preventing death conditional on severe disease - so in an important sense, the 95% figure is an underestimate of the relevant risk. In particular, the AstraZeneca vaccine has much better than 67% relative risk reduction of severe COVID.
It would be nice to have better information on prevention of transmission and asymptomatic infection too, but my understanding is that they're good enough that the challenge in reaching is almost entirely the fraction of people vaccinated (i.e. politics and public communications).