VerdictPal · editorial desk · updated 5 Sep 2026VerdictPal

Compare · Two models, head-to-head

Pick two models. See the diff.

Composite scores, benchmark ranks, capability grids, and pricing per million tokens. All sourced from the same data that powers the model atlas.

Tools Models

Claude Fable 5.1 vs GPT-6 Astra

Model A

Model B

MODEL A

Claude Fable 5.1

Anthropic · Claude Fable

Composite 63Intel 693 rows2 sources

Anthropic's 1 Sep 2026 Mythos-class refresh of Fable 5. Same $10 / $50 per 1M tokens, cache reads $0.25 per 1M. 1M context, 128K output. Live Vals Index 68.83% — still #1, ahead of Opus 5 and GPT-6 Astra. Live AA Intelligence Index v4.2 is 57 at max + default fallback. Do not compare that 57 to the Sept 1 v4.1 headline of 66.

MODEL B

GPT-6 Astra

OpenAI · GPT-6

Composite 60Intel 674 rows2 sources

OpenAI's 3 Sep 2026 flagship. API list $10 / $50 per 1M tokens, 1.05M context, 128K output, knowledge cutoff 30 Apr 2026. Vals Index 66.61% on the live board; AA Intelligence Index v4.2 is 55 at max effort. ChatGPT ships it as GPT-6 Pro on eligible plans.

Claude Fable 5.13stats won

Tied2stats

GPT-6 Astra2stats won

Spec showdown

Capacity, price, freshness.

Claude Fable 5.1vsGPT-6 Astra

Composite scores are within 5 points — 63 for Claude Fable 5.1 vs 60 for GPT-6 Astra. The choice comes down to capability profile and price. Claude Fable 5.1 has the higher Vals/AA intelligence score (69 vs 67).

Composite score
Claude Fable 5.163Winner on this rowGPT-6 Astra60
Intelligence (Vals/AA)
Claude Fable 5.169Winner on this rowGPT-6 Astra67
Context window
Claude Fable 5.11MGPT-6 Astra1MWinner on this row
Max output
Claude Fable 5.1128KGPT-6 Astra128K
Input price / 1M (lower wins)
Claude Fable 5.1$10GPT-6 Astra$10
Output speed (AA default API)
Claude Fable 5.1—GPT-6 Astra64 t/sWinner on this row
Time to first token (AA default API)
Claude Fable 5.1—Winner on this rowGPT-6 Astra384.30s

Composite score

Intelligence (Vals/AA)

Context window

Max output

128K

Input price / 1M (lower wins)

$10

Output speed (AA default API)

—

64 t/s

Time to first token (AA default API)

—

384.30s

Capability grid

What each model can do.

Modalities

Claude Fable 5.1GPT-6 Astra

Text●●

Image●●

Audio——

Video——

Code●●

Tool use●●

Reasoning●●

Access

Claude Fable 5.1GPT-6 Astra

API●●

Consumer app●●

Open weights——

Managed cloud●●

On-device——

Family profile

Top score per benchmark family.

Reasoning

Agentic

Benchmark ranks

Every shared benchmark, side by side.

Reasoning

Artificial Analysis Intelligence Index#11/187 · #18/187

57%

55%

Agentic

Vals Index#5/23 · #8/23

68.83%

66.61%

Dossier facts

Dates, sources, fineprint.

Claude Fable 5.1GPT-6 Astra

ProviderAnthropicOpenAI

FamilyClaude FableGPT-6

Release date2026-09-012026-09-03

Knowledge cutoff2026-06-012026-04-30

Context window1M1M

Max output128K128K

Input price /1M$10$10

Output price /1M$50$50

Statussolidflagship

Composite score6360

Intelligence score6967

Intel sourcevalsvals

Benchmark rows34

Source count22

Freshnessfreshfresh

Pricing checked2026-09-052026-09-05

Ecosystem

Which tools wrap each model.

Claude Fable 5.1

claude

GPT-6 Astra

chatgpt

Verdict

Which model to actually pick.

Open Claude Fable 5.1's dossier Open GPT-6 Astra's dossier