# A Tiny Cost Model for LLM + WhatsApp Automations (Bring Your Own Rates)

> Source: <https://dev.to/ujjwal_dubey_9/a-tiny-cost-model-for-llm-whatsapp-automations-bring-your-own-rates-14lc>
> Published: 2026-09-30 02:36:32+00:00

*I'm a builder at NxFlowAI, a Mumbai AI automation agency. This post contains no vendor prices on purpose. Prices change, and I don't want you copying a number from me. You supply the rates from each provider's own pricing page.*

When people ask what AI automation costs Indian small businesses, they usually get a range. A range hides the useful part: which lines scale with volume and which don't. Here is a small script that makes those lines explicit, so you can see what happens to the monthly bill if enquiries double. For how we describe engagement types, see [what AI automation costs Indian small businesses](https://www.nxflowai.com/pricing) on our pricing page (it has no numbers, so this post is the arithmetic).

## 
  
  
  The idea

Split the running cost into three kinds of line:

- 
**Fixed per month:** platform seat or plan, hosting, monitoring.
- 
**Per message:** template messages you send on WhatsApp. Per Meta's documentation, businesses are charged per delivered template message, with rates set by template category and country, and non-template messages in an open customer service window are not charged. Read the current rules at[Meta's pricing page](https://developers.facebook.com/docs/whatsapp/pricing) .
- 
**Per AI call:** input and output tokens for each model call, times your provider's rates.

## 
  
  
  The script

## 
  
  
  How to read the output

Run `monthly()` and `double_it()` with your real rates and counts, then look at two things:

1. 
**Which line grew?** Fixed lines don't grow when volume doubles; message and model lines do. A quote that hides these inside one monthly fee is telling you nothing about growth.
2. 
**Which line is missing?** If your vendor's monthly fee doesn't say whether it covers Meta's charges and model usage, ask. It is a common source of surprise.

## 
  
  
  What the script cannot tell you

- The **build** cost: that depends on how many systems and exceptions are involved, and a script can't price it.
- The **value** side: what a recovered enquiry is worth. Do that arithmetic first; our[free workflow-mapping guide](https://www.nxflowai.com/blog/how-to-audit-business-workflow-before-ai) is a starting point.
- The **rules** side: Meta says pricing changes for some message types take effect on 1 October 2026, so re-read its page before trusting any number, including the ones you type in.

If you extend the script (retries, media messages, multiple numbers), I'd like to hear what you added.