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Comparison

Worthune vs CalcXML

CalcXML is a hosted calculator library with an unusually wide set of integration options — iframes, an AJAX-loaded div, overlays, and web service calls — aimed at financial institutions and the agencies that build their sites. Worthune serves financial models through a REST API, an MCP server, and one embed script, and publishes a specification, test cases, and an audit record for each. The real split is integration breadth against published evidence.

Every claim below about CalcXML carries the page it was read from and the date. Oldest check on this page: .

Worthune

Financial planning models delivered as a REST API, an MCP server, and embeddable calculators, each with a published spec and a per-run audit record.

Developers and product teams at fintech, wealthtech, banking, and AI companies.

CalcXML

A hosted library of financial calculators embedded into customer websites.

Financial institutions, advisors, and agencies building client sites.

Side by side

Sourced facts only. Where a cell says a vendor does not publish something, that means we looked at the page named in the sources below on the date shown and it was not there — not that the answer is no.

WorthuneCalcXML
How it is deliveredREST API, MCP server, and a one-script-tag embedHyperlinks, iframes, an AJAX-loaded div, popup and lightbox overlays, plus HTTP POST with XML and SOAP or REST web service calls where the customer hosts the pages
Programmatic APIYes — REST and MCP, no key required for the three sample modelsYes — HTTP POST with XML, and SOAP or REST web service calls
Pricing modelSubscription; three models free with attribution, no per-run meteringNot stated publicly; the developer page directs prospects to sign up or make contact
Entry priceFree for three models; $199/month for the full catalogNot stated publicly
Published specification per calculatorYes — three in full publicly, the rest with a subscription; every input contract publicNot verified(not checked yet)
Published test casesYes — 250 cases per model, downloadable as JSONLNot verified(not checked yet)
Constants with primary sources and check datesYes — every constant carries a primary source and the date it was last checkedNot verified(not checked yet)
Per-run audit recordYes — SHA-256 over model, spec version, inputs and outputs, returned with every runNot verified(not checked yet)
Free tierThree models, no signup and no key, attribution requiredNot verified(not checked yet)

Where CalcXML is stronger

More ways in, and a long track record with financial institutions

Hyperlinks, iframes, popups, overlays, an AJAX-loaded div, HTTP POST with XML, and SOAP or REST calls where you host the pages — that is more integration surface than we offer, and it matters when a web team has constraints rather than preferences. They have also been serving this market far longer than we have.

When Worthune is the wrong choice

If breadth of calculators is the requirement

A hosted library aimed at covering every consumer money question will out-cover us on count. We are the wrong pick when the goal is filling a resource section, and the right one when someone downstream has to demonstrate a number is correct.

Our case

Where we think the difference actually matters

This section is our opinion rather than sourced fact, and it is marked that way on purpose — the table above is what a source URL can settle, and this is what it cannot.

A price you can read on the page

Ours is published and so is the free tier: three models answer with no signup, no key, and no conversation. A buyer can evaluate the actual product before anyone knows they were looking, which we think is how developers prefer to buy.

Evidence, not just output

Each model ships a versioned written specification, the exact cases the verification harness runs, and the constants it consumed with their primary sources and check dates. That is what a vendor-risk reviewer is actually asking for.

Built for assistants too

The same models answer over MCP, so an AI copilot can call the arithmetic and cite the spec version and the sources rather than predicting digits.

Provable after the fact

A SHA-256 record comes back with every run, over the model, spec version, inputs, and outputs. Store it and recompute it later to show where a number came from.

Questions

Common questions

What does CalcXML cost?
Not stated publicly. We checked the developer documentation page — where an integrator would look — on the date shown in the sources below, and it directs prospects to sign up or make contact rather than listing prices. That is not a criticism; it is how most vendors in this category operate. It does mean a like-for-like cost comparison is not something either of us can give you from public information.
Does CalcXML have an API?
Yes. Their developer page documents HTTP POST with XML and SOAP or REST web service calls, alongside the embedding options, with the customer hosting the input and result pages in that mode.
What is the actual difference for a developer?
Both can put a calculator on a page. The difference shows up afterwards: whether you can read the specification of what was computed, download the cases it was tested against, see the primary source for each constant, and hand a reviewer a record that proves a specific number came from a specific version.
Can I evaluate Worthune without a sales conversation?
Yes. Three models — emergency-fund, relocation, and side-business — answer over the API, the MCP server, and the embed script with no signup and no key.

Sources

Every claim above, and where it came from

Product names and trademarks belong to their owners and are used here only to identify the products compared. Nothing on this page implies endorsement or affiliation. Found something out of date? Tell us at support@worthune.com and we will re-check it.

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