Earned-Value (EVM) Lite Calculator

The problem this kills

Earned-value management is the gold standard for telling whether a project is ahead or behind, over or under budget - and whether it will still land on budget when it's done. But getting those numbers usually means buying heavyweight PM software, wrestling a fragile spreadsheet full of hidden formulas, or asking a controller to recompute everything by hand every reporting period.

So most teams skip it. They eyeball "we're about 60% done" against "we've spent about 70% of the budget" and hope. By the time the overrun is obvious, it's too late to react.

This tool gives you real earned-value rigor - SPI, CPI, and a forecast of the final cost - without the enterprise price tag or the brittle spreadsheet. You feed it the three numbers you already track per task or phase, and it does the math, explains what each index means, and refuses to publish anything until a human PM has reviewed and signed off.

What you'll build

A small, private web app for you and your team:

• Import a plan from a spreadsheet or CSV: per-task or per-phase planned value (the budgeted cost of the work), % complete, and actual cost to date.
• Automatically compute earned value (planned value x % complete), then the core indices: SPI (schedule performance), CPI (cost performance), and EAC (estimate at completion - what the whole project will cost if current performance holds).
• A plain-language read-out that translates every number ("CPI of 0.85 means you're getting 85 cents of value for every dollar spent - you're over budget").
• A PM approval gate: nothing is published until a named human reviews the % complete inputs and the computed indices and clicks approve.
• A published EVM report per project and reporting period, plus a clean CSV export in the columns your finance or PMO system expects.

What's inside the Implementation Plan

• A copy-paste runbook you drop straight into Claude Code - no coding experience needed.
• It opens by interviewing you about your business - your projects, how you measure % complete, your reporting periods, your cost conventions, and your edge cases - so the tool is tailored to how you actually run projects, not a generic template. It reads a short spec back to you and waits for your thumbs-up before building anything.
• Step-by-step build prompts you paste in one at a time, each producing a working piece of the app.
• The exact earned-value formulas, the plain-language explanations baked into the UI, and the approval workflow.
• A "No API yet?" fallback so you can build and use the whole thing today from a spreadsheet, with a CSV export back out - no integration required.

The governance it includes (this is the point)

Earned-value numbers drive real decisions and end up in front of sponsors, so the integrity of the data matters as much as the math. This plan builds in:

• Login so only your team can open the tool.
• Row-level security so each organization only ever sees its own projects and reports.
• A complete audit trail - who imported the data, who approved the report, and exactly when.
• A hard human-in-the-loop approval gate - the tool drafts the indices and read-out, a named PM reviews the % complete inputs and the math, and only an approved report is published.
• Duplicate guards so the same project + reporting period can't be processed or published twice.
• A built-in reminder that % complete must be an honest input, not an invented one - the read-out is only as trustworthy as the progress you feed it.

Who it's for

Project managers, PMO analysts, and program controllers who want genuine earned-value discipline - SPI, CPI, and a defensible cost forecast - without buying or learning enterprise PM software. If you can keep a spreadsheet of planned value, % complete, and actual cost, you can run this.

You've got this - paste the first prompt and let the agent interview you.