Planomy
Free embeds

Put a finance calculator on your site

Compound growth, mortgage payoff and FIRE number, packaged to drop into any page. Configure one below, watch the preview, copy the line of HTML. They run entirely in the visitor's browser — no cookies, no storage, no tracking, no requests to anyone but the widget file itself.

Licence: free to embed on any site, commercial or not — just keep the "Powered by Planomy" link.

Open the full planner — free Build the embed code

The widgets are one calculation each. Planomy itself is the whole picture — accounts, contributions, taxes, Social Security and a retirement date that moves when you change an assumption. It is free forever with no account and no card, and your plan is saved in your own browser rather than on our servers. Plus ($6/month) only adds syncing across devices, bank sync and a larger AI assistant allowance.

Build your embed

Everything here is optional — the defaults are a working embed. The preview is the real widget, loaded the way your page loads it, and the code below updates as you change anything.

Calculator
Appearance
"Match the visitor" follows their device setting.
Leave empty to fill the column it sits in.
Planomy blue
Repaints the chart, slider and attribution link. If it would be unreadable on the widget's own background, the widget lifts it just enough to stay legible.
Starting values

What your visitors see before they touch anything. Only values you change end up in the code.

Live preview

Full width

The widget sizes itself to its container, not the viewport, so a narrow column gets the stacked layout automatically.

Paste this on your page

One line, anywhere in your HTML. The script replaces itself with an iframe at that exact spot and keeps its height in sync, so the widget never scrolls inside its own box. 

<script src="https://planomy.net/js/embed.js" data-planomy-embed="compound-growth" async></script>

Or a plain iframe, if scripts are blocked

Many CMSs strip <script> tags. Each widget is also a normal page, so an iframe works on its own — it just cannot resize itself, so the height below is measured from the preview at the preview's current width. That matters: the widget stacks into one column below about 560px, so a narrow sidebar needs roughly twice the height of a full-width page. Set Maximum width above to your column width before you copy, or the bottom of the widget — the credit link included — is cut off. The script version resizes itself and never has this problem. The caption under it is the credit we ask for: it sits in your own page, so readers still see where the calculator came from if the frame ever fails to load. 

<iframe src="https://planomy.net/embed/compound-growth"
        title="Compound growth calculator by Planomy"
        width="100%" height="640" style="border:0" loading="lazy"></iframe>
<p><a href="https://planomy.net/calculators/compound-growth?utm_source=embed&amp;utm_medium=caption&amp;utm_campaign=embeddable-calculators">Compound growth calculator</a> by Planomy</p>

Every option, if you would rather hand-write it

The builder emits these for you. On the script tag they are data-* attributes; on an iframe URL they are query parameters (?theme=dark&rate=6). All optional.

Option Values
theme light or dark. Left off, the widget follows the visitor's operating-system setting.
accent A hex colour without the # — accent=0f766e. Repaints the chart, slider, focus ring and attribution link; text and surfaces keep their tuned contrast. A colour that would fall below 4.5:1 on the widget's own background is lifted towards white or black until it clears it, so the credit stays readable in both themes.
data-max-width Script tag only: caps the iframe width in pixels. On a plain iframe, use style="max-width:640px" instead.
compound-growth values initial (10000), monthly (500), rate % (7), years (20)
mortgage-payoff values balance (320000), rate % (6.5), payment (2100), extra (200)
fire-number values spending (60000), swr % (4), assets (150000), monthly (3000), age (32), rate % (5)

/embed/compound-growth.html works too, but it redirects to the extensionless URL the builder emits, so linking straight there saves every visitor a round trip.

What these do and do not do

  • The maths. Each widget uses the same model as its full calculator on Planomy: compound growth, mortgage payoff and FIRE number. Results are before tax; compound growth is nominal, the FIRE projection is in today's dollars.
  • Privacy. No cookies, no localStorage, no analytics, no network calls once the widget file has loaded. Nothing a visitor types leaves their browser, and nothing about your visitors reaches us — Planomy only counts a privacy-safe pageview when somebody clicks through to our own site.
  • Accessibility. Every input is labelled, the sliders and fields are keyboard operable with a visible focus ring, and the result is announced to screen readers as it changes.
  • Licence. Free to embed on any site, including commercial ones. No account, no key, no cost. Keep the "Powered by Planomy" link visible and followable. Do not present the widget as your own product or strip the attribution.
  • Not advice. They are estimates for planning intuition, not financial, tax or investment advice.

Want a different calculator packaged this way? See the full set — tell us which one you need and it can be added.

Planning your own retirement, not just writing about it?

The widgets answer one question each. Planomy answers the one they are all standing in for: given your accounts, contributions, taxes and Social Security, when can you actually stop working? It uses the same 2026 IRS and SSA figures published on this site.

Free forever, no account and no card. Your plan is saved in your own browser, not on our servers.

Open the planner