Assuming you know the difficulty level, hash value, and mining reward
This has nothing to do with your transaction time.Quote
how can you know how long the getting one confirm will take if you pay the average transfer fee (50%)? Even roughly ..
https://bitcoinfees.earn.com/ gives an estimate.Quote
What I want to know is formula for calculating transaction time(getting one confirm time).
There is no "formula", it depends on other transactions and their fees.Thank you.
But is there at least a reference number?As you know, sometimes there has been a lot of change in transaction time due to recent large hash rate fluctuations.(cause of BCH..) Like in this situation, we need an objective formula to refer to.
You can look at the mempool, and when it's not too crowded, then the transaction will be faster and it will be also cheaper. I like this site, I think it's the best site out there for the mempool:
https://jochen-hoenicke.de/queue/#30d
As you see the mempool is pretty nice right now to transact. Legacy transactions are cheaper and segwit transactions even cheaper. That big spike must have been one of these spam attacks because it doesn't make sense.