Embeddable website calculators.
For finance professionals and bloggers
Embed intuitive, generic modeling calculators designed for the UK market. Give your website visitors a clear, high-level estimate of financial scenarios, capture their self-reported inputs and route their inquiries straight to your inbox.
See It In Action
A live preview of how the simulator looks and feels when embedded directly on your website.
A High-Value Touchpoint
Deploy a seamless, illustrative calculator that starts the conversation and positions your team as the essential next step.
UK-Centric Logic
Modeled around UK tax bands, annual allowances and the State Pension gap to provide realistic, illustrative scenarios rather than generic global calculations.
A Conversation Starter
Offers a high-level, mathematical sketch of standard UK financial scenarios. It is explicitly designed for general education rather than precise tax profiling, giving your team the ideal opportunity to introduce your professional services and address the user's specific, regulated advice needs.
Zero Friction Leads
Capture warm intent passively. Once the user is engaged with the illustrative forecast, they seamlessly transition into a direct inquiry.
Transparent by Design
Plan58 is a utility-first micro-SaaS engineered by a UK web developer, not a massive, legacy software corporation. To achieve high-fidelity modeling within complex UK tax and pension logic, these calculators are built and rigorously QA-tested using advanced Agentic AI frameworks (powered by Google's Antigravity).
While this ensures highly sophisticated and context-aware logic, these tools are strictly generic, mathematical modeling utilities. They are designed to spark user engagement and capture basic, self-reported metrics, not to serve as absolute calculations or compliant financial advice. You get a lightweight, AI-optimized engagement tool for your website; your professional expertise provides the final, regulated numbers.
Select a Simulator to Embed
Review our suite of UK scenario-based modeling calculators below. Click through to evaluate any calculator's user experience. Each tool includes an on-page snippet generator so you can start a risk-free, 7-day trial with zero credit card required.
UK Retirement Pot (DC & DB) Income Drawdown
- Include a partner Yes
- Retirement age 58
- State pension age 68
- Defined benefit income £8,500
- Defined benefit age 58
- State pension amount £12,500
- Pension pot value £85,000
Early Retirement ISA & GIA Drawdown Bridge
- Part-time gross salary £16,000
- Age work stops 55
- Pension access age 58
- Desired net annual income £35,000
- Capital value (taxed) £55,000
- Annual growth rate (taxed) 7%
- Capital value (tax free) £125,000
60% Tax Trap Simulator: Mapping The £100k Allowance Taper
- Gross salary 125,000
- Cash bonus 20,000
- P11D Benefits in Kind 8,000
- Other taxable income 2,500
- Pension type Salary sacrifice
- Pension contribution amount 15%
- Number of children 2
Mortgage Overpayment vs. ISA Compounding
- Mortgage balance £225,000
- Mortgage term 25 yrs
- Investment return 8%
- Overpayment or investment amount £650
Adjusted Net Income vs Higher Income Child Benefit Charge
- Salary £85,000
- Bonus £10,000
- Salary sacrifice amount 15%
- Number of children 2
- SIPP contribution £2,500
Inflation-Adjusted Compounding
- Initial Capital Balance £55,000
- Monthly contribution £350
- Investment period 15 yrs
- Annual growth rate (AGR) 10%
- Inflation rate 2.5%
- Lump sum amount £9,000
- Lump sum year and month 9