Compare / head-to-head

Claude Fable 5vsStep 5 Preview

Claude Fable 5 leads 5 of 5 shared benchmarks. Step 5 Preview is 16.2x cheaper per token. Both offer a 1M-token context window.

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
5 – 0
Claude Fable 5 leads
Cheaper per token
Step 5 Preview
16.2x cheaper, input + output
Larger context
Tie
both 1M tokens
Providers
2 providers
Anthropic · StepFun
Claude Fable 5
Anthropic · released 2026-06-09
textvision
Context
1M
Max out
128K
Input /1M
$10 ↗
Output /1M
$50 ↗
Cached /1M
$1
Scores
44 · 11 core
Step 5 Preview
StepFun · released 2026-09-20
textvisionvideo
Context
1M
Max out
64K
Input /1M
$1 ↗
Output /1M
$2.7 ↗
Cached /1M
$0.05
Scores
5 · 4 core
Quality

Benchmark matrix

BenchmarkClaude Fable 5Step 5 PreviewΔEdge
Reported by both · 5
LMArena Elo1504.3 ↗1453.7 ↗+50.6Claude Fable 5
LMArena Agent (LMArena)0.0821 ↗0.0048 ↗+0.1Claude Fable 5
LMArena Vision (LMArena)1308.8 ↗1259.7 ↗+49.1Claude Fable 5
LMArena WebDev (LMArena)1625.3 ↗1570.2 ↗+55.1Claude Fable 5
Terminal-Bench 4.0 (Vals AI)41.4% ↗31.8% ↗+9.6 ptClaude Fable 5
Only Claude Fable 5 reports · 39
SWE-bench Verified95% ↗not reported——
GPQA Diamond85.9% ↗epoch runnot reported——
APEX-Agents (Mercor)63.6% ↗not reported——
AutomationBench17.4% ↗not reported——
Blueprint-Bench 238.6% ↗not reported——
Chess Puzzles (Epoch AI run)41% ↗epoch runnot reported——
CursorBench72.9% ↗not reported——
DeepSWE v1.1 (Datacurve)69.9% ↗not reported——
EBR-bench (Epoch AI run)39.5% ↗epoch runnot reported——
FrontierCode (Diamond)29.3% ↗not reported——
FrontierMath Tier 4 v2 (Epoch AI run)90.2% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)87% ↗epoch runnot reported——
FrontierSWE V2 (Proximal Labs)47% ↗not reported——
Furniture Assembly (Epoch AI run)35.8% ↗epoch runnot reported——
GDP.pdf29.8% ↗not reported——
GSO Opt@1 (GSO)76.5% ↗not reported——
Legal Agent Benchmark (Harvey's Held-Out Set)13.3% ↗not reported——
LiveBench Agentic Coding (LiveBench)62.2% ↗not reported——
LiveBench Coding (LiveBench)86% ↗not reported——
LiveBench Data Analysis (LiveBench)80.5% ↗not reported——
LiveBench Instruction Following (LiveBench)75.8% ↗not reported——
LiveBench Language (LiveBench)90.7% ↗not reported——
LiveBench Mathematics (LiveBench)96% ↗not reported——
LiveBench Reasoning (LiveBench)89.7% ↗not reported——
MirrorCode (Epoch AI run)63.9% ↗epoch runnot reported——
Mystery Game Puzzles (Epoch AI run)52% ↗epoch runnot reported——
OfficeQA Pro57.9% ↗not reported——
OSWorld-Verified85% ↗not reported——
OSWorld-Verified (XLANG)86% ↗not reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)100% ↗epoch runnot reported——
SAGE (Vals AI)51.9% ↗not reported——
SimpleBench (SimpleBench)81.9% ↗not reported——
SimpleQA Verified70.7% ↗epoch runnot reported——
SWE-Bench Pro80% ↗not reported——
SWE-rebench 2026-05-15 to 2026-07-01 (Nebius)64.5% ↗not reported——
tau2-bench Banking Knowledge (Sierra)39.7% ↗not reported——
Terminal-Bench 2.184.3% ↗not reported——
Vending-Bench 2 (Andon Labs)5680.26 ↗not reported——
WeirdML (Håvard Tveit Ihle)91.9% ↗not reported——
Only Step 5 Preview reports · 0
Step 5 Preview reports nothing Claude Fable 5 does not.
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Fable 5 minus Step 5 Preview in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecClaude Fable 5Step 5 PreviewEdge
Context window1M tokens1M tokensTie
Max output128K tokens64K tokensClaude Fable 5
Input price / 1M$10 ↗$1 ↗Step 5 Preview
Output price / 1M$50 ↗$2.7 ↗Step 5 Preview
Cached input / 1M$1 ↗$0.05 ↗Step 5 Preview
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$60$3.7Step 5 Preview
Modalitiestext · visiontext · vision · videoStep 5 Preview
Released2026-06-092026-09-20—
Cited benchmark scores445—
Reliability

Provider status

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