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Right, let’s sort your retirement out.
Complicated pension maths, made simple. Plan your retirement accurately, by yourself, in about five minutes.
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Greatest retirement app by far. There’s truly nothing else out there that offers this level of insight and ease of use.
Finally, a UK based retirement app to help me plan for the future. I love the multiple scenarios and how it optimises your drawdown for UK tax.
Look, it’s not your fault.
The system’s a mess.
- “Your pension is on track”... on track for what? Nobody ever says.
- Jargon soup: crystallisation, PCLS, MPAA. Deliberately confusing so you stop asking questions
- A projection PDF that might as well say “good luck, here’s a pie chart”
- That nagging feeling you should be doing something but having absolutely no idea what
- Shows you the age your pot runs out. No sugarcoating, no panic. Just clarity.
- Plain English. The kind you’d use explaining it to a mate.
- Year-by-year projection with three scenarios you can actually read.
- Plan as a couple. Both pensions, both taxed properly, one shared target.
- Property, ISAs, inheritance, side income — the full picture, not just the pension bit.
- From £7.99/mo. Less than your Friday coffee habit.
Simple answers first.
Depth when you want it.
Isaac starts with three questions and gives you one clear number. These are its real screens, for an example couple, taken straight from the app. Drag the slider, pick a year, press play. In the app, it’s your numbers.
The age your money lasts to, in one number
No jargon, no score. Isaac takes what you have and what you pay in, and tells you the age your money lasts to. It is the first thing you see every time you open the app, with the chart that gets you there.
Retire earlier or later: drag a slider and watch
Want to stop work sooner? Drag the retirement age and the whole plan redraws as you go, with the point your money runs out marked on the chart. Use the slider below to step through what the app showed.
All your pensions, stacked up year by year
Workplace pots, an old pot you had forgotten, a final salary scheme, the State Pension. Isaac stacks them for every year of retirement so you can see the gaps before they arrive.
Every year of your plan, written down
One row per year: what your pots are worth, how much they grew, what went in or came out, and the tax. Retirement is marked where it begins.
Cash flow: every pound in, every pound out
One year at a time, every pound in on the left and every pound out on the right. Step through retirement and watch the State Pension arrive and the drawdown ease.
Historical backtest: your plan replayed through every year since 1871
Monte Carlo rolls a thousand imagined futures. The historical backtest replays the real ones: this plan started in every year since 1871, through the crashes, booms and inflations that actually happened, in the order they came, and the events that shaped each.
Chronology: pick any year and see it in full
What comes in, what goes out, what is left in each pot, and the tax, for any year you choose. The scrubber along the bottom marks every event on the way.
Inheritance tax planning, including pensions from April 2027
The estate, the allowances and the bill at any age, with gifts, reliefs, life insurance and the April 2027 pension rule modelled. Here: a £1.3m estate and where the taxable zone starts.
Tax-efficient drawdown: which pot to draw first
Guaranteed income first, then your flexible savings in the order you choose. Isaac compares each order on how long the money lasts and the tax over your whole retirement.
Pot by pot: every pot, how it grows, when it is used
Every pot you hold, how it grows, and when each one is used up. Yours and your partner’s, in today’s money or nominal.
A taste, not the full list. Isaac also does Monte Carlo stress tests, what-if comparisons, the Retirement Year Planner, property and buy-to-let, business owners’ company funds, PDF reports and Excel export, and plans for couples. See everything in the user guide.
“I opened my pension statement once. Didn’t understand a word. Put it back in the drawer. That drawer is now load-bearing.”
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Five minutes. Honestly.
We timed it. Twice.
The basics
Age, pension pot, contributions, spending. Four things. Two minutes.
The “oh right” moment
Isaac projects your money year by year to 100. Three scenarios: optimistic, base, cautious. Most people feel better after seeing it, not worse.
Add the details
Partner, property, ISAs, side income, inheritance. Whatever matters to you.
Have a play
Drag the sliders, compare scenarios, export a PDF. Keep tweaking until you find a plan that works.
Help shape the future.
Join the Good Ideas Club.
Isaac is built for you, so we build what you ask for. Tell us what we should add next, what to fix, or what you'd love to see. Vote on ideas from the community, and see what we're working on.
See What We're BuildingFair questions.
Straight answers.
Start free. Upgrade when
you’re ready.
Have a look around for free. When you want the full toolkit, Premium’s there. No pressure, no time limit on the free plan.
- Unlimited scenarios
- Workplace, personal, final salary & State Pensions
- Property, savings & ISAs
- Spending curve & big purchases
- Partner details in your plan
- Extra income, inheritance & tax settings (England/Scotland)
- Projection chart (optimistic / base / cautious) & income breakdown
- “What would it take?” for retirement age, spending and saving
- Already Retired mode
- Excel export & cloud sync
- Monte Carlo stress test & historical backtest
- What if & scenario comparison
- Year-by-year detail
- PDF report
New to Isaac? Try Premium free for 3 days when you set up your plan. No payment is taken.
A financial adviser charges ~£150 an hour. Isaac Premium is £7.99 a month — and it does the maths first.
- Everything in Free
- Monte Carlo stress test across 1,000 market paths
- Historical backtest: your plan replayed from every retirement year since 1871
- Cash flow view: each year’s money from source to spend
- What if — try a change and compare
- Scenarios side by side
- Year-by-year detail & full-screen charts with live sliders
- PDF report to keep or share with your adviser
- Retirement Year Planner — the tax year you stop work, to the day
- Chronology, Pot by pot & wealth tracker
- Business owners: your company’s retained funds, dividends, liquidation or sale compared
- Tax-efficient drawdown
- Inheritance tax planning: gifts, reliefs & life insurance
- Partner linking — your partner joins free
- Every future feature
Retirement planning, without the jargon
Practical guides to help you understand pensions, tax, and planning — written in plain English.
How Much Do I Need to Retire in the UK?
PLSA benchmarks, pension pot sizes, the things people forget, and how to work out your actual number. A 2026 guide with real figures.
How Safe Is My Retirement Plan? Two Ways to Stress-Test It
Why a steady-growth projection cannot tell you, sequence-of-returns risk with a worked example, what a 90% chance means, and the four levers that move it.
UK State Pension Explained: How Much You’ll Get & When
Full amounts for 2026/27, qualifying years, pension age changes, the triple lock, and why filling NI gaps might be the best investment you make.
You’ve read this far.
You obviously care.
Let’s do this.
Five minutes from now you could know exactly where you stand.
Prefer your desktop? Open the web app →
Real reviews,
from real planners.
Isaac is an educational planning tool - not financial, investment, tax, or legal advice. We’re not authorised or regulated by the FCA. Projections are based on what you put in and aren’t guarantees (pensions and investments can go down as well as up). For proper decisions, always talk to a qualified, FCA-regulated adviser. We do the maths. They do the advice. Between the two, you’re sorted.