Claude Fable 5 vs o4-mini — Side-by-side pricing
Side-by-side API pricing and tokenizer details for Claude Fable 5 (Anthropic) and o4-mini (OpenAI).
Side-by-side pricing
| Feature | Claude Fable 5 | o4-mini |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input (per 1M tokens) | $10.00 | $1.10 |
| Output (per 1M tokens) | $50.00 | $4.40 |
| Context caching | Yes — 90% off cached tokens | No |
| Batch API discount | 50% off | 50% off |
| Context window | 1M tokens | 200K tokens |
| Tokenizer | Anthropic tokenizer (Opus 4.7+) | o200k_base (tiktoken) |
ⓘ o4-mini: Deprecated by OpenAI. API access shuts down 2026-10-23; calls will error after that date. Prices are no longer listed on OpenAI's pricing page and could not be re-verified from a vendor source.
Real-world cost example
1,000 API requests per month, each with 500 input tokens and 200 output tokens (500K input + 200K output total).
Claude Fable 5
$15.0000
Input: $5.0000 +Output: $10.0000
o4-mini
$1.4300
Input: $0.5500 +Output: $0.8800
o4-mini is 90% cheaper for this workload — saving $13.5700 per month at this volume.
Frequently asked questions
No, o4-mini is cheaper for the typical workload above. At $1.10/1M input and $4.40/1M output tokens, it costs $1.4300 versus $15.0000 for Claude Fable 5 — a 90% difference.
Claude Fable 5 supports a 1M token context window. o4-mini supports a 200K token context window. A larger context window lets you include more text — documents, conversation history, or code — in a single API call.
Claude Fable 5 supports context caching (90% off repeated tokens). It offers a 50% Batch API discount. o4-mini does not support context caching. It offers a 50% Batch API discount.
No, they use different tokenizers. Claude Fable 5 uses the Anthropic tokenizer (Opus 4.7+), while o4-mini uses o200k_base (tiktoken). Different tokenizers split text differently, so the same prompt will produce different token counts on each model — the effective cost difference may be larger or smaller than the per-token price difference alone suggests.
Claude Fable 5 (Anthropic): $10 input / $50 output per 1M tokens. o4-mini (OpenAI): $1.1 input / $4.4 output per 1M tokens. Rates shown before caching or batch discounts.
For an 80% output / 20% input workload — typical for code generation or long-form writing — Claude Fable 5 costs $42.0000 per 1M total tokens and o4-mini costs $3.7400. o4-mini is 91% cheaper for this pattern. For your exact ratio, paste a real prompt into the calculator above.
Claude Fable 5 has a 1M-token context window — approximately 750K words or ~3K pages of standard text. o4-mini has a 200K-token context window — approximately 150K words or ~600 pages. (Estimates assume ~0.75 words per token.)
Calculate costs for your actual prompt
Paste your prompt into the calculator and get exact token counts using each model's real tokenizer — all in your browser.
Open calculator