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Subscription or API: which is cheaper?

How many messages do you send a day, and how long are they? The calculator estimates what that usage would cost on the API and compares it with subscription prices.

Prices updated October 2026
plan-vs-api.tsSubscription vs API
tokens
Includes the growing chat history.
tokens

How we compare

Every chat message resends the conversation history, so the average input grows through the day. The calculator treats half of that input as cache reads (as the apps do) and adds the answer. The result is the equivalent monthly API cost.

What a subscription gives beyond price

  • Web, desktop and mobile apps, search, files, memory and projects.
  • Tools such as Claude Code and Codex included in the plan.
  • A fixed price: no surprises on the bill.

The limits

Plans aren't unlimited. Claude uses 5-hour usage windows and weekly limits; Max 5x and Max 20x give 5 and 20 times Pro's usage. ChatGPT also caps messages per window on its strongest models.

Reference prices: Claude Pro $20, Max 5x $100, Max 20x $200, ChatGPT Plus $20 and Pro $200 per month. Local prices and taxes may differ.

Quick answers

Claude ProClaude MaxChatGPT Plus

Frequently asked questions

Is Claude Pro worth it?

It depends on your pace. 40 messages a day on Sonnet 5.5 would cost about $10 a month on the API; on Opus 5.5, about $20. Pro pays off if you use more than that, want the apps and Claude Code, or prefer a fixed price.

Does a subscription include API access?

No. A subscription covers the plan's apps and tools; the API is billed separately, per token.

Estimate based on public prices as of October 2026. Token counts vary with the text and the model; check the official pricing page before you decide.