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Free Calculator · Anthropic Claude API

Claude API Cost Calculator

Plug in your monthly input and output token volume. Get a side-by-side monthly cost for Claude Sonnet 4, Opus 4.1, and Haiku 4.5 at list price. Browser-only math, no signup, rates as of 2026-05.

Your monthly Claude usage

Sonnet 4
$0/mo
Opus 4.1
$0/mo
Haiku 4.5
$0/mo

List-price math only. Prompt caching can cut real bills 30-70% on workloads with a stable system block. The deep audit models your actual usage with caching included.

Published Claude API rates (as of 2026-05)

Source: anthropic.com/pricing — verify before committing to a contract
Model Input ($/MTok) Output ($/MTok) Best for
Claude Sonnet 4$3.00$15.00General agents, code, default production
Claude Opus 4.1$15.00$75.00Hardest reasoning, multi-step planning
Claude Haiku 4.5$1.00$5.00Classification, extraction, high-volume Q&A

Get the 2-page Claude API cost cheat-sheet

One-page rate reference + one-page "5 ways your Claude bill goes 3x over list price" — most common waste patterns we see in real audits. PDF sent to your inbox.

When list-price math isn't enough
Get the LLM Bill Triage Deep Report
One-shot $299 audit of your real Anthropic (or OpenAI) usage. 30-day cost-driver scan, prompt-bloat heatmap, model-routing wins, fix recipes. PDF in 24 hours. Money-back if total identified monthly savings is under $299.
Get the deep audit — $299 →
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How the math works

For each model: monthly_cost = (input_tokens × input_rate / 1,000,000) + (output_tokens × output_rate / 1,000,000)

Example: 5 million input tokens + 1 million output tokens on Sonnet 4 = (5 × $3) + (1 × $15) = $30/month at list price. Same workload on Opus 4.1 = (5 × $15) + (1 × $75) = $150/month. Same workload on Haiku 4.5 = (5 × $1) + (1 × $5) = $10/month.

The 15x cost gap between Haiku and Opus is real and rarely justified for the same task — most production agents over-pay 2-4x by defaulting to the highest-tier model when the workload doesn't need it. That's the single biggest line in most Claude bills we audit.

What this calculator doesn't model

Frequently Asked Questions

Which Claude API rates does this calculator use?

Published per-million-token rates as of 2026-05 from Anthropic's pricing page. Sonnet 4: $3 input / $15 output. Opus 4.1: $15 / $75. Haiku 4.5: $1 / $5. Anthropic occasionally updates these — always cross-check against anthropic.com/pricing before signing a contract.

How do I know my input and output token volume?

From console.anthropic.com, open the Usage tab and export your last 30 days. The export breaks down input vs output tokens per model. If you don't have a billing relationship yet, a rough heuristic: 1,000 tokens is about 750 English words. A typical chat turn is 200-500 input tokens and 100-300 output tokens.

Does this include prompt caching discounts?

No. List-price math only. Prompt caching offers up to a 90% discount on cache reads — for prompts with a stable system block, real bills are often 30-70% below this estimate. If you want a workload-specific cached-price model, run the $299 LLM Bill Triage on your actual usage export.

Which Claude model should I pick?

Haiku 4.5 for high-volume classification, extraction, and short Q&A — fastest and cheapest. Sonnet 4 for general agents, code generation, and most production use — the default in 2026. Opus 4.1 for the hardest reasoning, multi-step planning, and tasks where one wrong answer is expensive — 5x Sonnet, only worth it where it earns the markup.

Is my data sent anywhere?

No. Token volumes and rate math run locally in your browser. The page fires an anonymous pageview beacon and CTA-click events so we can measure whether the calculator is useful — no inputs, no email (unless you submit one to the cheat-sheet form), no raw IP stored.

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