Are UK take-home calculators too complicated?

eskbanker

https://forums.moneysavingexpert.com/discussion/comment/81886659#Comment_81886659

Is that different though? The HMRC one is undoubtedly an outlier, being in iterative questionnaire format, but the others seem to be in a broadly similar style to what you have in mind, although you've perhaps spent more time analysing the pros and cons of what's currently available?

InspectahDave

Thanks for the interest here. I appreciate you're trying to understand the motivation a little more, so I'll caveat this with the fact that this is based on opinion around user experience and the "feel" of current offerings, which is very hard to quantify.

There are ways of doing this, such as
1. Measuring how many clicks are required to get to the result
2. Counting the number of fields/option boxes
, and these are things that I've deliberately tried to reduce. Going back to the original question, or maybe the root of my thinking, is about balancing this trade-off correctly between configurability and usability.

My thinking is that functionally, many of them overlap, yes. The difference I’m focusing on is more about visual clarity and immediacy — keeping everything on one screen, minimal visual noise, and instant updates as you adjust inputs.

It’s subtle, but when you’re modelling trade-offs, that clarity can make the process feel less cognitive-heavy and may reduce friction for some people.

https://forums.moneysavingexpert.com/discussion/comment/81886681#Comment_81886681

poseidon1

One final thought relates to accuracy of these free calculators and to what extent they are meticulously maintained and updated in an ever changing tax landscape, by people with appropriate in depth tax knowledge.

To illustrate I had a go at using a couple of the links supplied by @eskbanker.

To that end I had a go at a couple of simple CGT computations on Pie and UKtaxcalclators, both purporting to have specific tabs for the purposes.

Pie proved to be a complete waste of time and a prime example of amateur hour. Clicking on capital gains, produced a calculation that deducted the income personal allowance of £12570 and applying 20% income tax on the net gain. Utter rubbish of course, but how would clueless members of the public realise this?

As for UKtaxcalculators their CGT calculator got off to a reasonable start in asking all the right questions. However on a 'what if' calculation for a taxable gain for the current tax year 2025/26, the gain was ultimately taxed at a 10% rate, which was abolished October 2024. Clearly, out of date and again misleading to the general public.

With all due respect to the OP, I see no justification for adding yet another simplified version of some of the free ( but dodgy) calculators already doing the rounds, unless he is a duly qualified and experienced tax practitioner versed in all aspects of personal tax and prepared to meticulously maintain such a calculator as necessary.

In the meantime, HMRC' s calculators or those provided by HMRC accredited third party self assessment filing providers ( 41 at last count) are the reliable if not necessarily approachable on a 'quick and dirty sanity check' basis.

monkey-fingers

This feels like reinventing the wheel.

The MoneySavingExpert one allows you to do all the things above, plus student loans

https://www.moneysavingexpert.com/tax-calculator/

penners324

The hmrc app has a tax calculator. Which is ok.

UK Tax Calculators is an better one.

InspectahDave

The comments in this thread were really helpful and prompted me to run a comparison between the available tools to understand their feature completeness and accuracy. I've summarised the work in this thread.

Gaberdeen

I'm a fan of the LTTM (listen to Tax Man) calculator, although if you're interested I can relay my own teeny bugbears about their calculator that would be improvements and list some of the things I really like.

Bugbears

1. They hadn't updated their annual allowance from 40k to 60k- they did this after I emailed and pointed out it was wrong

2. They have no "salary sacrifice" button for pension contributions (or any other kind of deduction) - which ultimately changes NI and Income Tax calculations quite significantly compared with relief at source calculations - this will inevitably become even more complicated in 2028 when the £2000 limit on NI tax relief comes into force.

3. As per the above, if you can work out the net taxable salary sacrifice, you could display not only total pension contributions, but total tax-saved compared to tax on the gross amount - which although isn't crucial, would be a welcome feature.

Things I like about LTTM

1. Break-down in tax by marginal rate i.e seeing how far into the 42% tax bracket you are - gives you the impetus to optimise
   
2. Yearly/Monthly/Weekly data presentation, great for quick reference
   
3. Summary of all deductions as well as a comprehensive breakdown

InspectahDave

https://forums.moneysavingexpert.com/discussion/comment/81910569#Comment_81910569

Thanks for this. This matches what I saw in that salary sacrifice was actually one of the biggest sources of divergence when I compared the calculators. I've collected my findings in a feature matrix across several tools (including LTTM - listed as "UK Salary Calculator" in the table) to see which ones support different pension mechanisms and inputs. I've attached a section from the article here in case it's useful (I can share the link if needed). It helped clarify where some of the differences in results come from.

EDIT: replaced the spreadsheet feature matrix screenshot with a snippet from an article showing the comparison of pension plan calculations only.

Cobbler_tone

As someone with several elements of salary sacrifice, flexible pension contributions and taxable benefits, I use this one. It always gets it right within 10p a month. Ultimately, if you put rubbish in you'll get rubbish out.

The Salary Calculator - Take-Home tax calculator

Now if someone could explain the tax system! I have never had as much 'trouble' as I've had this year. My code is going up and down like a yo-yo and at the moment they think I owe them but by my calculations they owe me a little. The only contributor can be my changing pension contributions via SS. Everything else (salary, other SS and taxable benefits) is the same every month. My tax bill is on track to be nearly £10k less than last tax year. I'm sure it'll all correct itself.

laptopguy111

I think simple is best to be honest too much noise is going to put people off