Claude Fable 5 Paid vs 
GPT-5.6 Luna Paid
Claude Fable 5 vs GPT-5.6 Luna compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.
Claude Fable 5 — full profile › · GPT-5.6 Luna — full profile ›
Prices & specs refreshed from live data · OpenSourceAI.tech
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
Claude Fable 5 vs GPT-5.6 Luna specs
| Spec | Claude Fable 5 | GPT-5.6 Luna |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Type | Proprietary | Proprietary |
| Context window | 1M tokens | 1.1M tokens |
| Input price | $10/M | $1/M |
| Output price | $50/M | $6/M |
| Vision / multimodal | Yes | Yes |
| Tool / function calling | Yes | Yes |
| Self-hostable | No (API only) | No (API only) |
| License | Proprietary | Proprietary |
Feature comparison
| Capability | Claude Fable 5 | GPT-5.6 Luna |
|---|---|---|
| Open weights (downloadable) | ✗ | ✗ |
| Self-hostable | ✗ | ✗ |
| Runs fully offline | ✗ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✓ |
Benchmarks: Claude Fable 5 vs GPT-5.6 Luna
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How Claude Fable 5 and GPT-5.6 Luna score
| Criterion | Claude Fable 5 | GPT-5.6 Luna |
|---|---|---|
| Cost-efficiency | 2.0 | 4.0 |
| Context window | 5.0 | 5.0 |
| Openness | 1.5 | 1.5 |
| Self-hosting | 1.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
Claude Fable 5 Paid
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and...
GPT-5.6 Luna Paid
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
Frequently asked questions
Claude Fable 5 vs GPT-5.6 Luna — which is cheaper?
GPT-5.6 Luna is cheaper on output ($6/M vs $50/M).
Which has the larger context window?
GPT-5.6 Luna offers the larger context window (1.1M tokens).
Claude Fable 5 vs GPT-5.6 Luna — which should I pick in 2026?
Choose GPT-5.6 Luna for the lower output price ($6/M vs $50/M). It also gives you the larger 1.1M context window.
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