★ AI chatbot · cost estimate

How Much Does It Cost to Build an AI Chatbot?

A demo chatbot takes a weekend. A chatbot customers trust takes retrieval that finds the right document, evaluations that catch regressions, and guardrails for when the model does not know. The estimator prices the second one.

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1What are you building on?

Platform

Responsive web app

Design

A polished component library, lightly themed.

2Who builds it?

Team

One person, low overhead, slower calendar time

Blended hourly rate

$/ hour

A starting point. Type the rate from your actual quote.

3Pick the features

Your estimate: $15,400–$34,100.

Want a second opinion? Send it to me and I'll tell you which features I'd cut to ship weeks sooner.

Send me this estimate

What people forget to budget for

Evaluation

Without a test set of real questions and expected answers, every prompt change is a guess. Budget time to build one and run it on every change.

Ingestion

PDFs with tables, scanned documents and stale content cause most bad answers. Cleaning and chunking the data is often more work than the chat UI.

Running cost

Token spend scales with usage. Model routing and caching decide whether your unit economics work.

How the estimate works

Each feature has a range of hours for a senior engineer building production-quality software. Those hours scale with the number of platforms, then the estimate adds what every real project needs on top of writing features.

build  = setup + design + Σ(feature hours × platform factor)
hours  = (build + 20% QA + PM overhead) × 1.15 contingency
cost   = hours × hourly rate
weeks  = hours ÷ productive hours per week

Ranges, not single numbers, because the honest answer depends on details nobody knows yet: how clean the third-party APIs are, how many design rounds you want, how often scope moves. If someone quotes a single number without asking those questions, the range is hiding in their change requests.

Building for web and mobile is not twice the work with React Native: the backend, business logic and much of the UI code are shared. That is why the platform factor for web plus mobile is about 1.5, not 2.

Worked example

Take an AI chatbot MVP with 6 features (sign-up & login, admin panel, file uploads & media, dashboards & charts, ai feature (llm), marketing site), built by a senior freelancer at $60/hour:

Worked example
Line	Hours
Feature build (incl. setup and design)	172–380
QA, project management, contingency	85–188
Total	257–568

That comes to $15,400–$34,100 over roughly 9–19 weeks. Deferring admin panel alone would save about $4,310.

Hours by feature

The ranges the estimator uses, before platform factor and overhead. The features founders most often underestimate are payments, permissions and admin tooling: none of them are visible in a demo, and all of them are needed the week after launch.

Hours by feature
Feature	Covers	Hours
Sign-up & login	Email + Google/GitHub OAuth, password reset, sessions	16–32
Admin panel	Manage users, content and orders without touching the DB	32–64
File uploads & media	Direct-to-storage uploads, image resizing, limits	16–32
Dashboards & charts	User-facing analytics, aggregates, exports	24–56
AI feature (LLM)	Chat, summaries or generation with RAG over your data, plus evals	40–100
Marketing site	Landing page, pricing page, SEO basics, blog	12–32

Questions founders actually ask

How much does it cost to run an AI chatbot each month?

It depends on traffic, prompt size and model. Use the LLM API Cost Calculator to estimate the monthly bill for your expected volume.

Do I need to fine-tune a model?

Rarely for an MVP. Retrieval over your documents plus a good prompt covers most use cases, and it is cheaper to change.

Can I use an off-the-shelf chatbot builder instead?

For an FAQ bot, yes. Build custom when the bot needs your data, your permissions or actions inside your product.

How accurate is this estimate?

For a well-scoped MVP, expect the real number to land inside the range, assuming scope stays put. The bigger risk is scope creep, not the estimate: every feature added mid-build costs more than it would have up front.

Why is this higher than the agency quotes I've seen?

Teaser quotes usually exclude QA, project management, revisions and a buffer for the unknown. This estimator includes all four, so it is closer to what you will actually pay.

Do AI coding tools make an MVP cheaper?

They speed up boilerplate, tests and UI scaffolding. They do not remove product decisions, integrations, edge cases or debugging in production, which is where most of the hours in this breakdown sit.

Estimate by product type

Or start from scratch with the full MVP cost estimator.

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Fine print

Tools: on the house.
Engineer: by the hour.

Building it isn't free either, but it can be faster than you think. Send me the breakdown and I'll tell you what I'd ship first.

I'm Himanshu, an AI and full-stack engineer. I build MVPs, AI agents and the growth plumbing around them for early-stage startups.

Hire me →My projects