---
title: "SaaS MRR Growth Projection Calculator"
method: POST
path: "/api/v1/tools/saas-mrr-growth-calculator"
tags: ["business"]
---

# SaaS MRR Growth Projection Calculator

`POST /api/v1/tools/saas-mrr-growth-calculator`

## Request

- Base URL: `https://calcfleet.com`
- URL: `https://calcfleet.com/api/v1/tools/saas-mrr-growth-calculator`
- Auth: none declared

Model SaaS MRR growth with monthly compounding: add new revenue, subtract churn, apply expansion. See projected ARR and months to any revenue milestone.

## Request body

- object
  - `startingMrr` number, required
  - `newMrrPerMonth` number, required
  - `monthlyChurnPct` number, required
  - `monthlyExpansionPct` number, required
  - `months` integer, required
  - `targetMrr` number

## Response `200`

Successful calculation result.

- object
  - `result` object, required: Structured calculation output (fields vary per calculator).

## Other responses

- `400`: Invalid input — the issues array contains Zod validation errors.
- `403`: Forbidden — an Authorization: Bearer cf_… key was supplied but is invalid.
- `404`: Unknown tool slug.

---

[API](https://skmtc.dev/calcfleet/apis/calcfleet-financial-calculators-api.md) · [All operations](https://skmtc.dev/calcfleet/apis/calcfleet-financial-calculators-api/llms.txt) · [OpenAPI document](https://skmtc.dev/calcfleet/apis/calcfleet-financial-calculators-api/revisions/cd9abd595bbe?raw)