AI Chatbot Cost Calculator

Chatbots get expensive because every turn resends the conversation so far. This calculator models that growing history and returns a realistic cost per conversation and per month.

Inputs

Result

$401

per month

$0.0267 per conversation · $13.35 per day

Input tokens per conversation
6,360
Output tokens per conversation
1,080
Cost per conversation
$0.0267
Cost per 1,000 conversations
$26.70
Cost per day
$13.35
Cost per month (30 days)
$401
Cost per year
$4,873

Disclaimer: Model availability, pricing and specifications may change. Verify pricing directly with the provider before making business decisions. Preset rates reflect published list prices last reviewed August 2026; choose “Custom pricing” to enter your own rates.

Formula

  • Turn n input = system prompt + n user messages + (n − 1) bot replies
  • Conversation input = sum of every turn's input
  • Conversation cost = input cost + (bot reply tokens × turns) × output rate

Methodology

Most chatbots are stateless behind the scenes: each turn resends the entire conversation so the model has context. Input tokens therefore grow quadratically with the number of turns, which is why a ten-turn chat costs far more than twice a five-turn chat.

The calculator sums the input for every turn rather than multiplying a single average, so the growth is modelled properly. Output is linear because the bot writes one reply per turn.

Trimming history, summarising older turns or caching the system prompt all reduce the input side, which is where most of a chatbot's cost sits.

Example: a six-turn support chat

  1. With a 400-token system prompt, 60-token user messages and 180-token replies, six turns send about 5,700 input tokens in total and produce 1,080 output tokens.
  2. At $2.50 input and $10.00 output per million: $0.0143 + $0.0108 = about $0.025 per conversation.
  3. At 500 conversations a day that is roughly $12.55 a day, or about $377 a month.

Frequently asked questions

Why does a longer chat cost more than proportionally?

Every turn resends the whole history, so the tenth turn pays for the previous nine. Input tokens grow with the square of the turn count unless you trim or summarise the history.

How do I cut chatbot costs without hurting quality?

Cap the history to the last few turns plus a running summary, shorten the system prompt, cache it if your provider supports caching, and cap reply length.

Should I include a cheaper model for simple messages?

Routing greetings and simple lookups to a small model and escalating only hard turns typically cuts total spend substantially with no visible quality loss.

Are these prices always up to date?

The presets reflect widely published list prices and are reviewed periodically, but providers adjust them and offer discounts for batch processing, cached input and committed spend. Model availability, pricing and specifications may change. Verify pricing directly with the provider before making business decisions.

What happens when a provider launches a new model?

Model names and rates live in one central configuration, so a new model appears in every relevant dropdown as soon as it is added. Page URLs stay provider-based rather than version-based, so no link ever goes stale when a model generation changes.

Does the calculator send my data anywhere?

No. Every calculation runs in your browser, so nothing you type is uploaded, stored or logged.

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