try dyno-blitzer https://github.com/pcapr/dyno-blitzer https://github.com/pcapr/dyno-blitzer which scales up dynos, runs a load test and tells you how many dyno

try dyno-blitzer https://github.com/pcapr/dyno-blitzer https://github.com/pcapr/dyno-blitzer which scales up dynos, runs a load test and tells you how many dynos you'll need to support x concurrent users.