Pricing comparison

Claude Fable 5 vs GPT-5.5 nano

Per-token pricing, full-workload cost ladders, and monthly volume projections. Numbers sourced directly from each provider's rate card.

Anthropic

Claude Fable 5

Input
$10.00 / 1M
Output
$50.00 / 1M
Cached input
$1.000 / 1M
Context
1M
Max output
128K

OpenAI

GPT-5.5 nano

Input
$0.25 / 1M
Output
$1.50 / 1M
Cached input
$0.025 / 1M
Context
400K
Max output
128K

Cost per request

Four common workload shapes, input tokens and a 1:2 output ratio (a standard chat/completion pattern). Long-context surcharges apply automatically where the provider charges them.

ScenarioTokens (in / out)Claude Fable 5GPT-5.5 nanoWinner
Short prompt100 / 200$0.0110$0.0003GPT-5.5 nano
Typical request1,000 / 2,000$0.1100$0.0033GPT-5.5 nano
Long document10,000 / 5,000$0.3500$0.0100GPT-5.5 nano
Large prompt100,000 / 10,000$1.5000$0.0400GPT-5.5 nano

Monthly bill at scale

Projected monthly cost at typical request volume, assuming the "typical request" shape above (1k in, 2k out).

TrafficReq / monthClaude Fable 5GPT-5.5 nanoDelta
Small SaaS1,000$110.00$3.25GPT-5.5 nano -$106.75
Growing product10,000$1,100$32.50GPT-5.5 nano -$1,068
Heavy usage100,000$11,000$325.00GPT-5.5 nano -$10,675

Which should you use?

For the typical chat-shape request (~1k input, 2k output), GPT-5.5 nano comes out 3285% cheaper. If you're picking one as the default, that's usually the right choice on cost alone.

GPT-5.5 nano wins on both sides of the bill - cheaper input and cheaper output. If the quality gap is in your favour, there's no cost argument for the other side.

Context window differs: Claude Fable 5 holds 1M of input vs 400K on the other side. If you regularly push past the smaller ceiling, the comparison ends there.

Live cost calculator

Type in any token counts - both prices update instantly. Uses base input/output rates (no cache discount, no long-context tier).

Claude Fable 5

$0.0350

per request

GPT-5.5 nano

$0.0010

per request

GPT-5.5 nano is $0.0340 cheaper per request (97.1% less).

Try both in the estimator →

Drop your actual prompt in, tokens are counted with the provider's own tokenizer, and the dollar number matches what lands on your invoice.

Frequently asked

Which is cheaper, Claude Fable 5 or GPT-5.5 nano?
On a typical 1,000-input / 2,000-output request, GPT-5.5 nano costs ~$0.0033 vs ~$0.1100 on Claude Fable 5. Input or output rates can flip the answer for very lopsided workloads - see the cost ladder above.
What's the difference in per-token pricing?
Claude Fable 5 charges $10.00 per 1M input tokens and $50.00 per 1M output tokens. GPT-5.5 nano charges $0.25 / $1.50 per 1M.
Which has the bigger context window?
Claude Fable 5 is larger (1M) vs 400K on the other.
Is there a cached-input discount on either?
Claude Fable 5 caches at $1.000 per 1M (90% off). GPT-5.5 nano caches at $0.025 per 1M (90% off). Workloads with repeated static prefixes see the biggest savings.
How fresh is this comparison?
Claude Fable 5 was re-verified on 2026-07-01 and GPT-5.5 nano on 2026-04-29 against each provider's published rate card. Calcis re-checks every row on a rolling schedule and re-deploys when a provider changes pricing.

Claude Fable 5 verified 2026-07-01 · GPT-5.5 nano verified 2026-04-29. Rate cards at Anthropic and OpenAI.