Put a UBWHY calculator on your own site

Who this is for

Publishers who already write about money and whose readers arrive at a question a calculator answers better than a paragraph: independent finance publications, newsletters with a website, investing creators with an owned web presence, financial-education businesses, and fee-only advisers who publish explanatory content.

It is a poor fit if you need bespoke financial logic, a regulated workflow, a tax engine, or a calculator built to your own model. That is software development, and it is not what this is.

How it works

1. You choose one of the four published calculators below.
2. UBWHY hosts it and gives you one line of HTML: an iframe pointing at a URL on ubwhy.com, configured for your site and your name.
3. You paste it into the article or template where it belongs. It sizes itself to the column it sits in.
4. The calculation runs in your reader's browser, against the same model the public UBWHY calculator uses. When UBWHY corrects a model, your embed is corrected in the same release.

There is no script to install, no account to create and nothing to keep updated. If you later stop, you delete the iframe.

A live embed

This is the Investment Fee Drag calculator, running in a frame exactly as it would on your site. Enter figures and calculate: nothing is sent anywhere, and nothing is stored.

Open the embed in its own tab to see exactly what is served, orthe full calculator on UBWHY for the method, the worked example and the model record.

The four calculators

Every one is published, in use on this site, and documented. The pilot covers one of them.

• Investment Fee Drag Calculator

  How much could fees reduce your future investment value?

  Converts recurring percentage and fixed investment costs into a projected end-value effect under your own assumptions, and separates the amounts deducted from their compounding effect.

  View the live calculator

• Drawdown Recovery Calculator

  How much must an investment gain after a loss, and how long could recovery take under the assumptions you enter?

  Converts a loss into the gain required to reverse it, and separates regaining the old balance from catching the plan the portfolio was on before the loss. Where new money is added, it keeps contributions apart from investment return.

  View the live calculator

• Real Return after Fees and Inflation Calculator

  Your balance grew, but did your purchasing power grow after fees and inflation?

  Projects a nominal balance after your own fee assumptions, translates it into start-date purchasing power, and compares it with the inflation-adjusted value of every amount contributed at the date it was contributed.

  View the live calculator

• Opportunity Cost Calculator

  What projected financial value do you give up by choosing one use of the same money over another?

  Projects two financial uses of the same available money over the same horizon, under your own annual value-change assumptions and each option’s own upfront cost, and reports the difference in projected ending value, when one path overtakes the other, and what the lower path would need to close the gap.

  View the live calculator

The Investment Fee Drag calculator has the embed delivery today. Extending it to another of the four is part of onboarding rather than a separate project; say which one you want and it is scoped in the same conversation.

How these are built

Deterministic

The same inputs always produce the same outputs. No forecast, no market data, no randomness, no model that changes under a reader mid-session.

Documented

Every calculator publishes its formulas, its timing conventions, its assumptions, its limitations, a worked example and a dated correction history. The method is reachable from inside the embed.

Private by construction

A calculation makes no network request and writes no cookie, nolocalStorage, no sessionStorage and no URL parameter. Your readers' figures never leave their browsers, so there is nothing for you to disclose and nothing for UBWHY to hold.

Nothing inside the calculator measures anything, and no reporting on what your readers enter is offered, because collecting it would break the sentence above.

Accessible

Keyboard operable, landmarked and labelled, with a text equivalent beside every chart, to the same baseline the public calculators hold.

Responsive

Renders from 360px upward without horizontal scrolling.

Pilot price

€990one-time setup

€79 per monthhosting and maintenance

These are pilot prices for the first customers. They are a test of what this is worth, not a published rate card, and they are not derived from a market survey.

Invoiced manually, in euros. There is no card form, no subscription mechanism and no automatic renewal.

What a pilot includes

• One published UBWHY calculator, chosen from the four below.
• Hosted by UBWHY, embedded in one page or template on one approved domain.
• The same deterministic calculation model the public UBWHY calculator uses, with no second implementation and no separate figures.
• Documented methodology, reachable from inside the embed.
• Responsive rendering from 360px upward, and the same keyboard and screen-reader behaviour as the public calculator.
• Every calculation in the reader’s browser: no request, no cookie, no storage, no measurement.
• Maintenance and model corrections for the duration of the pilot.
• Your name in the embed header, and the choice of whether it carries a “Calculator by UBWHY” line.
• Manual onboarding: a short scoping exchange by email, then UBWHY configures and activates it.

What it does not include

Stated here rather than discovered later. The scope is narrow on purpose: it is what makes the price and the maintenance commitment deliverable.

• Custom financial formulas, bespoke calculators or customer-specific model logic.
• Tax calculations of any kind.
• Accounts, logins, saved scenarios or lead capture.
• A reporting dashboard, or any measurement of what your readers enter.
• Third-party scripts, tracking pixels, tag managers or advertising integrations inside the embed.
• Arbitrary CSS or HTML, or changes to result wording, assumptions, warnings or the order figures appear in.
• Affiliate links, referral parameters or product promotion inside the calculator.
• CRM integration, API access or a self-service embed builder.