Claude Fable 5 vs GPT-5.6 Luna

At a Glance

Compare
Pricing and Limits
Input priceFrom · USD / 1M tokens$10.00Anthropic ↗ · Sep 3, 2026$0.20Openai ↗ · Sep 3, 2026
Output priceFrom · USD / 1M tokens$50.00Anthropic ↗ · Sep 3, 2026$1.20Openai ↗ · Sep 3, 2026
Context windowMaximum documented tokens1,000K1,050K
Model facts checkedAug 28, 2026View model evidence →Aug 28, 2026View model evidence →

Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →

Available Benchmarks

All benchmark results →
BenchmarkClaude Fable 5GPT-5.6 Luna
ARC-AGI-1verified-v1-613c385b0c93 · verified_score · leader98.50100% of row best · percent · Claude Fable 5 (XHigh)90.6792% of row best · percent · GPT-5.6 Luna 2026-07-30 (Max)
ARC-AGI-2verified-v2-be40992860f9 · verified_score · leader89.17100% of row best · percent · Claude Fable 5 (Max)59.5867% of row best · percent · GPT-5.6 Luna 2026-07-30 (Max)
LMArena Document Arenadocument-2026-09-13-a64ca3b12b6e · arena_rating · leader1,496.08100% of row best · rating · claude-fable-5; 95% CI [1488.22135990, 1503.94311259]; votes 8497; rank 51,456.9297% of row best · rating · gpt-5.6-luna-xhigh; 95% CI [1448.72029252, 1465.11301394]; votes 5766; rank 23
LMArena Vision Arenavision-2026-10-09-a64ca3b12b6e · arena_rating · leader1,323.95100% of row best · rating · claude-fable-5-high; 95% CI [1316.82313713, 1331.08571856]; votes 14175; rank 11,258.2495% of row best · rating · gpt-5.6-luna-xhigh; 95% CI [1250.82216689, 1265.66350676]; votes 11086; rank 58
LiveBench2026-06-25-90f8d44da965 · overall · leader86.55100% of row best · percent · claude-fable-5-max-effort · 20,255 output tokens / case77.0589% of row best · percent · gpt-5.6-luna-max · 21,799 output tokens / case
ToneBench2026-10-17-10-task-e9c76358afb2 · overall_score · unverified81.90100% of row best · points · Claude Fable 5 (high) · 24,076 output tokens / case78.8396% of row best · points · GPT-5.6 Luna (ultra) · 19,621 output tokens / case
Overall ResultCounted from the protocol-matched rows above5 benchmark winsOverall lead0 benchmark wins

Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.

Side-by-Side Facts

FieldClaude Fable 5GPT-5.6 Luna
DeveloperAnthropicOpenAI
FamilyClaude 5Gpt 5 6
ModelClaude Fable 5GPT-5.6 Luna
VersionClaude Fable 5GPT-5.6 Luna
Lifecycleactiveactive
Released2026-06-09Unknown
Knowledge cutoffUnknown2026-02-16
Input modalitiesText, ImageText, Image
Output modalitiesTextText
Context window1,000K1,050K
Total parametersUnknownUnknown
Active parametersUnknownUnknown
LicenseUnknownUnknown
Open weightsNoNo
API availableYesYes
Self-hostableNoNo
Provider accessAnthropic (Standard), Deepinfra (Standard), Openrouter (Standard)Openai (Standard), Openrouter (Standard)
Capabilitieschat, generation, reasoning, toolschat, generation, reasoning, tools

Claude Fable 5 Capabilities

chatgenerationreasoningtools
Serving providers3
Canonical IDanthropic/claude-fable-5

GPT-5.6 Luna Capabilities

chatgenerationreasoningtools
Serving providers2
Canonical IDopenai/gpt-5.6-luna

Primary Evidence

Sources and Freshness

Questions

Claude Fable 5 vs GPT-5.6 Luna FAQs

Is Claude Fable 5 or GPT-5.6 Luna better for coding?+

This comparison does not currently contain a protocol-matched coding benchmark for both Claude Fable 5 and GPT-5.6 Luna, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.

Which is cheaper, Claude Fable 5 or GPT-5.6 Luna?+

Claude Fable 5 is $10.00 and GPT-5.6 Luna is $0.20 per million tokens, so GPT-5.6 Luna is cheaper on this metric. Claude Fable 5 is $50.00 and GPT-5.6 Luna is $1.20 per million tokens, so GPT-5.6 Luna is cheaper on this metric.

Which has a larger context window, Claude Fable 5 or GPT-5.6 Luna?+

GPT-5.6 Luna has the larger sourced context window. Claude Fable 5 supports 1,000,000 tokens and GPT-5.6 Luna supports 1,050,000 tokens.

Which performs better in benchmarks, Claude Fable 5 or GPT-5.6 Luna?+

Claude Fable 5 leads the current overall benchmark count. The result uses 5 protocol-matched benchmarks from 3 publishers; it is not a universal quality score.

Can Claude Fable 5 or GPT-5.6 Luna be self-hosted?+

Both models have the same sourced self-hosting status: unsupported. Claude Fable 5 is not marked open weight; GPT-5.6 Luna is not marked open weight.

Can Claude Fable 5 and GPT-5.6 Luna understand images?+

Claude Fable 5 is documented with image input; GPT-5.6 Luna is documented with image input. This reflects supported input modalities, not vision quality.

Which can generate longer answers, Claude Fable 5 or GPT-5.6 Luna?+

Both models have the same sourced maximum output: 128,000 tokens each.

Do Claude Fable 5 and GPT-5.6 Luna support reasoning and tool use?+

Claude Fable 5: reasoning, tool calling, and image input. GPT-5.6 Luna: reasoning, tool calling, and image input. Feature support does not establish relative quality.

Which is available from more inference providers, Claude Fable 5 or GPT-5.6 Luna?+

Claude Fable 5 has 3 sourced provider routes; GPT-5.6 Luna has 2, so Claude Fable 5 has broader tracked availability.

Which offers better value, Claude Fable 5 or GPT-5.6 Luna?+

There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.

Send Feedback