MModelspectraIndependent AI Model Intelligence
Head-to-head · Updated 2026-09-08
Model Comparison · Head to Head

Claude Fable 5 vs GPT-5.6 Sol

Claude Fable 5 wins on Overall, Coding, Multimodal. Every numeric field is compared below, with a worked monthly-cost example and a pick rule for each use case.

VendorAnthropic / OpenAI
Data fields15+ dimensions
Updated2026-09-08
Read~9 min
01

Verdict at a glance

Bottom line: Choose Claude Fable 5 when coding depth, long-context reliability, lower refusal matter most; choose GPT-5.6 Sol when lower cost is the priority.

Choose Claude Fable 5 if you…

  • Strongest all-round reasoning
  • Reliable long-context recall
  • Top-tier coding
  • Best for: Deep reasoning, Long documents, Coding

Choose GPT-5.6 Sol if you…

  • Enhanced reasoning
  • Strong code generation
  • o-series architecture
  • Best for: Reasoning-heavy tasks, Coding, Math
02

Head-to-head aggregate scores

Scores are 0–100, aggregated from public benchmark information and independently weighted across three leaderboards. Rank is out of 22 tracked models.

Claude Fable 5 Higher overall
Anthropic · #1 overall
Overall95
Coding99
Multimodal97
VS
GPT-5.6 Sol
OpenAI · #11 overall
Overall72
Coding88
Multimodal80

Aggregated from public sources and independently weighted; methodology on the Terms page. Scores within 3 points are treated as statistically tied.

03

Specs & pricing — every field side by side

List API prices in USD per 1M tokens. The highlighted cell is the stronger value/capability on that row.

DimensionClaude Fable 5GPT-5.6 SolVerdict
VendorAnthropic (US)OpenAI (US)Different vendors
Released2026.062026.07GPT-5.6 Sol is newer
Overall (rank)95 · #172 · #11Claude Fable 5 +23
Coding99 · #188 · #3Claude Fable 5 +11
Multimodal97 · #180 · #11Claude Fable 5 +17
Context window1M1.05MGPT-5.6 Sol larger
Max output128K128KTie
Effective-context9888Claude Fable 5 more reliable
Input $/1M$10$5GPT-5.6 Sol cheaper
Output $/1M$50$30GPT-5.6 Sol cheaper
Cache discount90% off50% offClaude Fable 5 deeper
Speed~30 tok/s~25 tok/sClaude Fable 5 faster
TTFT1.2s2.0sClaude Fable 5 snappier
Function calling9293GPT-5.6 Sol ahead
Refusal rate~8%~14%Claude Fable 5 less restrictive
English9892Claude Fable 5
Chinese8274Claude Fable 5
Modalitiestext, imagetext, imageSame
Open weightsNoNoBoth closed
Fine-tuningNoNo
Free tierNo free tier; $5 credit to startNo free API tier
SOC2 / no-trainyes / yesyes / yes
Private deploymentNoNoNeither

Fields drawn from vendor public documentation and the Modelspectra 22-model dataset; speed varies with network, concurrency and prompt length. Verify current pricing before purchase.

04

Dimension-by-dimension analysis

Reasoning & overall intelligence

Claude Fable 5 leads the overall aggregate by 23 points (95 vs 72). That is a meaningful, not marginal, edge on hard, multi-step reasoning, while GPT-5.6 Sol remains a strong generalist that is not out of its depth on routine work.

Agentic coding

This is a clear gap: Claude Fable 5 scores 99 against 88. On multi-file edits, SWE-style tickets and long-horizon agent loops Claude Fable 5 needs fewer correction turns; GPT-5.6 Sol is still competent for scripts and assisted completion but trails as task complexity rises.

Multimodal

Claude Fable 5 leads multimodal 97 vs 80. Neither emits native video, so the comparison is about parsing images and documents, not generation.

Speed & latency

Claude Fable 5 is faster in interactive use: ~30 tok/s with 1.2s TTFT versus ~25 tok/s with 2.0s TTFT (about 1.2× the throughput). For conversational UIs where perceived responsiveness drives retention, that edge is a real product factor even when raw reasoning is lower.

Context: window vs usable recall

Nominal windows are 1M for Claude Fable 5 and 1.05M for GPT-5.6 Sol. Crucially, the larger nominal window does not win on usable recall: GPT-5.6 Sol advertises 1.05M but Claude Fable 5 scores higher on effective-context (98 vs 88), i.e. it actually retains more of what it was given.

Price & total cost

GPT-5.6 Sol is the cheaper API at $5/$30 versus Claude Fable 5 at $10/$50 per 1M input/output tokens — list input is about 2.0× lower. Cache discounts (Claude Fable 5 90% vs GPT-5.6 Sol 50%) shift the effective bill, worked out below.

Chinese vs English

English: Claude Fable 5 98 vs GPT-5.6 Sol 92. Chinese: 82 vs 74. Both are US-based models; for Chinese-first workloads also compare domestic models on the leaderboard.

Tool use & ecosystem

Function-calling score: Claude Fable 5 92 vs GPT-5.6 Sol 93, so GPT-5.6 Sol has the edge on structured tool use. Neither offers standard fine-tuning. Factor in existing SDK/plugin familiarity — switching cost often outweighs a few-point tool-use gap.

05

Cost worked example — same workload, real token math

Assume a production workload of 100M input + 30M output tokens per month, with 90% of input tokens served from cache. Figures use public list prices.

Scenario · per monthClaude Fable 5GPT-5.6 SolGap
List priceno cache applied$2,500100M in × $10  +  30M out × $50$1,400100M in × $5  +  30M out × $301.79×gap
With caching90% of inputs cache-hit$1,69090M cached in × $1  +  10M in × $10  +  30M out × $50$1,17590M cached in × $2.5  +  10M in × $5  +  30M out × $301.44×gap

Illustrative model; your input/output mix and cache-hit ratio change the result. Prices are list rates before any enterprise agreement.

06

Decision tree

IF the workload is agentic or multi-file coding and a wrong first pass is expensive  →  choose Claude Fable 5 (coding 99 vs 88).
IF you serve real-time users and latency is a product KPI  →  choose Claude Fable 5 (~30 tok/s, 1.2s TTFT).
IF you are cost-driven at scale on routine, high-volume workloads  →  choose GPT-5.6 Sol ($$5/$$30 per 1M in/out).
IF long-document recall has to be near-perfect  →  choose Claude Fable 5 (effective context 98 vs 88).
07

Frequently asked questions

Is Claude Fable 5 worth the higher price over GPT-5.6 Sol?
At list the input rate is 2.0x higher, but cache discounts and output pricing narrow the effective gap. Pay the premium when Claude Fable 5's stronger dimensions protect revenue; for routine volume GPT-5.6 Sol is the economical pick.
Does GPT-5.6 Sol's higher refusal rate matter in production?
GPT-5.6 Sol refuses about 14% of prompts versus 8% for Claude Fable 5. In unattended pipelines that means more retries, fallbacks and manual review, raising effective cost and latency even when the token price is lower.
How do costs compare at 100M tokens/month with caching?
At 100M input + 30M output with 90% of inputs cache-hit, Claude Fable 5 is about $1,690/month and GPT-5.6 Sol about $1,175/month after cache discounts ($2,500 and $1,400 at list).
Does the bigger context window actually matter?
Nominal windows are Claude Fable 5 (1M) and GPT-5.6 Sol (1.05M), but usable recall follows the effective-context score (98 vs 88). Prefer the higher effective-context model for long-document work where nothing can be missed.
Which handles multimodal inputs better?
Multimodal scores are 97 (Claude Fable 5) vs 80 (GPT-5.6 Sol), with modality coverage text/image versus text/image. Match the model to the input types your product actually receives.
What is the single-line recommendation?
Choose Claude Fable 5 for Deep reasoning, Long documents; choose GPT-5.6 Sol for Reasoning-heavy tasks, Coding.