You turned 42 in March and want to know whether your £180,000 in pensions plus the £35,000 in ISAs is enough for the retirement you actually want. MaxiFi can model that. So can Delphina. Here is how the two approaches differ.
MaxiFi was built for US financial planners and the people they advise. It models Roth conversions year-by-year, runs Social Security claiming strategies against your portfolio, handles Medicare premium cliffs, and projects Required Minimum Distributions from age 73. If you are a US household with $1m+ in tax-deferred accounts and you want to optimise the order of withdrawals over a 30-year retirement, MaxiFi is one of the better consumer tools for that specific job. The Monte Carlo engine runs thousands of scenarios with correlated asset classes and inflation paths.
Delphina does not attempt any of this. If you live in the US, the comparison is not close on this dimension.
Delphina was built for the UK. It uses HMRC rules: 25% pension tax-free lump sum, the annual allowance taper from £260,000, the State Pension forecast through your NI record, ISA subscription limits, and the dividend and capital gains allowances. The retirement number Delphina calculates is the UK number: roughly £580,000 for a moderate single-person retirement, around £815,000 for a couple, after State Pension.
More importantly, Delphina connects the plan to what you actually do. You do not type a hypothetical spending number into a planner and hope it matches reality. Delphina reads your real spending from your bank, projects forward using your actual savings rate, and tells you the gap. A 42-year-old spending £3,400 a month with £215,000 in pensions and £35,000 in ISAs gets a specific answer in Delphina, not a generic "you may be behind" warning.
MaxiFi treats retirement planning as a separate exercise from your daily money. You enter assumptions, the tool runs scenarios, you read the output. It is sophisticated about US tax but blind to whether you can actually sustain the lifestyle in the projection.
Delphina treats retirement as a continuation of your daily money. Your pension contribution this month shifts the projected retirement date in real time. A pay rise changes the picture the same day. If your mental model is "I want to know if I'm on track and what to do next", Delphina's design matches it. If your model is "I want to model 30 years of withdrawal order to optimise tax", MaxiFi's design matches that.
Pull your latest State Pension forecast from gov.uk and your most recent pension statement, then connect both to Delphina this week. The forecast and statement are free and take 15 minutes to gather. Once they are in, the gap between your current position and the moderate retirement number becomes a single line on the screen, and you can act on it.