Comparison methodology: This page reflects Delphina's view and publicly available information about each tool, checked against isaacmoney.com on 12 October 2026. Features and prices can change. Verify with each provider before you pay. Neither product provides regulated financial advice.
You have a retirement number, and you still cannot tell if you are fine. Isaac is a UK retirement calculator: you type in a pot and a spending figure, and it tells you the age your money lasts to. Delphina checks that number against the spending you upload, and tells you whether that retirement is funded.
Both can show a long forecast. Only Delphina checks it against the spending in the statements you upload.
A retirement calculator
You type in age, pension pot, contributions and a spending figure. Isaac also models ISAs, property, a partner and UK tax. It projects year by year to 100, across optimistic, base and cautious, and shows the age your money lasts to.
The spending figure is one you type in. It is not your transactions.
A verdict, not a typed-in number
You add your accounts and upload CSV or PDF statements. No bank login. Delphina uses that spending, not a single figure you type in, and tells you whether the retirement you want is funded, and what would have to change if it is not.
A retirement number built on a spending figure you typed is only as good as that figure.
Free to start. No card. No bank login.
Checked against Isaac's site on 12 October 2026. Isaac does scenario modelling, ISAs and UK tax. The difference is not that those are missing.
| Feature | Isaac | Delphina |
|---|---|---|
| What you get first | The age your money lasts to, from the figures you enter | A verdict on whether that retirement is funded by how you really spend |
| Where the numbers come from | You type in age, pot, contributions and a spending figure | You add your accounts and upload CSV or PDF statements. No bank login |
| Forecast | Year by year to age 100, optimistic, base and cautious | Forward projection from the balances and spending you add |
| ISAs, pensions, property, UK tax | Yes. England and Scotland tax bands. Couple, property and ISAs are in the model. | Yes. UK pensions, ISAs and the accounts you add |
| Scenarios | Yes, including what-if and side-by-side comparison on Premium | Yes. Change an assumption and see if the verdict moves. |
| Day-to-day spending | A spending figure and spending curve you enter. Not your transactions | The transactions in the statements you upload |
| Price | Free, no time limit. Premium £7.99/month or £79.99/year. New accounts can try Premium for 3 days, no payment taken | Free to start, no card. Wealth Builder £9.99/month. Investor £19.99/month |
| Regulated advice | No. Isaac says it is a calculator, not FCA regulated | No. Guidance, not regulated advice |
Prices checked on 12 October 2026. Check each provider's site before you pay.
Add your accounts, upload a statement, and see whether the retirement you want is funded by how you spend.
Get your verdict freeFree to start. No card. No bank login.
Yes. Isaac has a free plan with no time limit. Premium is £7.99 a month or £79.99 a year, and new accounts can try Premium for 3 days with no payment taken. Prices checked on isaacmoney.com on 12 October 2026.
Yes. Isaac models workplace, personal, final salary and State Pensions, plus property, savings and ISAs, and applies England or Scotland tax rules. Saying it ignores those is wrong.
No. Isaac uses the numbers you type in. Delphina does not connect to your bank either. You add accounts and balances yourself, and upload CSV or PDF statements so spending is categorised from those files.
Isaac gives you a retirement number, and that number is only as good as the spending figure you typed. Delphina takes the spending in the statements you upload and tells you whether the retirement you want is funded.