estimate smart fee - bitcoin fee estimates
Node running since September 1; updating once per 10 minutes
me - IPA fund at 1CrwjoKxvdbAnPcGzYjpvZ4no4S71neKXT
Feel free to use as an API. For anything bigger though, you should actually use bitcoind directly instead.
mempool + smart fee visualization
Code of the graph copy-pasted from https://estimatefee.com (with permission)