What could I retire on today? Calculator advice please.

Is there a website where I could put in the current value of my assets, any income streams and any pensions including when they will become payable which could then tell me how much a year I could receive if I were to retire now (or at some future point). I am not just after an annuity rate but something that for example would give the answer using a 4% rule and an inflation linked payment or be it with some risk / potential requirement to accept lower income to match with market conditions.

I will give my numbers as an example:
Age 48, Partner 52
State pension age 67 for both, both full entitlement.
Assets 550k in pensions, 50k in cash
300k flexible mortgage currently fully offset but allowing flexibility prior to age 55 in conjunction with TFLS.
Other income:
11.5k pa benefits (? index linked) until 2024
5k Lodger probably index linked until 2030 say

So in 2018 money: 16.5k from now to 2024, 5 k from 2024 - 2030, 8k from 2033 and 16k from 2037. Using the 600k pot and the offset mortgage as needed and say a life expectancy to mid 90s, what constant (index linked) annual sum could I aim for if I decided not to go back to work tomorrow?!