// in this post
Every L&D team gets asked the question it can't easily answer: did the training actually pay off?
The problem
Learning budgets get cut first because learning impact is the hardest to prove. "People liked it" is not a number a finance director respects. So most teams either guess at the return or avoid the conversation, and lose ground every budget round.
What it is
A calculator built on Kirkpatrick's four levels. You enter the real costs (design, delivery, salaries, technology) and rate the programme across reaction, learning, behaviour change and business impact. It turns that into a defensible ROI figure and a report you can export as a PDF and take into the room.
Who it's for
Learning and development professionals who need to show the value of their work in language the business already trusts.
How I made this
A calculator is a clear model plus a clean interface, so this was a design-then-build job, doable with Claude Design and Claude Code in an afternoon.
1. Decide the model, then design it. Work out what it should measure first, the real programme costs set against Kirkpatrick's four levels, then design the screen in Claude Design (claude.ai/design, in a browser or the Claude desktop app). You can skip the design step and describe it in words if you'd rather go straight to the build.
2. Build it. Hand it to Claude Code (Anthropic's coding assistant, which you run from your terminal or the desktop app) with a prompt like:
Build me a single-page web tool (static front end, all logic in the browser,
no backend) that calculates [the number you need to defend].
- Inputs: [the figures the user enters].
- Model: [the framework or formula it should use, e.g. Kirkpatrick's levels].
- Output: the headline number plus a plain-English readout and recommendations.
- Let the user export a clean PDF report (jsPDF does this well).
- Keep it to two minutes of work, not a spreadsheet.
3. What you get. A static front end (an index.html plus a small script and stylesheet): the maths runs in the browser, the PDF export uses jsPDF, no backend.
4. Put it online. I deployed it to Vercel (vercel.com, free at this size): connect a folder or a GitHub repo, or drag it in, and it's live on a URL in under a minute.
The arithmetic is the easy part. What makes it land is choosing a model the people you're presenting to already trust, so the number survives the meeting.