The Bitcoin mining with PC days are a long time ago gone and mining with your personal computer is not possible for most of the coins. But there are still coins profitable mining with CPU like Monero for example.
Monero price today is $96. If you mine Monero with coinhive you today you will get 0.00005565 XMR per 1M hashes.
I have been mining Monero a year ago when difficulty was lower and this is my results.
This video below is a good guide about how to mine Monero with CPU un Windows or Mac.
If you have AMD cards the most profitable Ethereum mining.
If you only have the CPU, an interesting option is to mine Bitcoin with Cryptotab Browser .
Basically, they are mining Monero with your CPU but will pay you in bitcoin according to the actual rate.
Another coin to mine with CPU is Nimiq or NIM. This coin unknows to most people is ranked 500 in coinmarket. It is very easy to mine NIM , just create a wallet on their official website and start mining from the bowsers.
If you go with ASIC a good option is Antminer Z9 mini. With this hardware which cost around $2000, you will be making back your investment in 4-5 months according to today difficulty. However, this is just an estimate because many miners are shipped every day and difficulty increases.
You should be aware that mining is a high energy consuming process that produces heat and a lot of fan noise. Also if you do not monitor your hardware heat and keep it under control, there is the risk of burning your hardware.
Let me know in the comments below, which is the best coin to mine now in 2018?