Compare / head-to-head

Claude Sonnet 5.5vsSeed-OSS-36B-Instruct

Claude Sonnet 5.5 leads 2 of 2 shared benchmarks. Claude Sonnet 5.5 has the larger context window (1M tokens).

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

Shared benchmarks
2 – 0
Claude Sonnet 5.5 leads
Cheaper per token
—
list price, input + output
Larger context
Claude Sonnet 5.5
1M tokens
Providers
2 providers
Anthropic · ByteDance Seed
Claude Sonnet 5.5
Anthropic · released 2026-09-28
textvision
Context
1M
Max out
128K
Input /1M
$2 ↗
Output /1M
$10 ↗
Cached /1M
$0.2
Scores
29 · 10 core
Seed-OSS-36B-Instruct
ByteDance Seed · released 2025-08-20
text
Context
512K
Max out
—
Input /1M
—
Output /1M
—
Cached /1M
—
Scores
18 · 12 core
Quality

Benchmark matrix

BenchmarkClaude Sonnet 5.5Seed-OSS-36B-InstructΔEdge
Reported by both · 2
GPQA Diamond95.6% ↗epoch run71.5% ↗epoch run+24.1 ptClaude Sonnet 5.5
OTIS Mock AIME 2024-2025 (Epoch AI run)100% ↗epoch run67.5% ↗epoch run+32.5 ptClaude Sonnet 5.5
Only Claude Sonnet 5.5 reports · 27
LMArena Elo1471 ↗not reported——
APEX-Agents (Mercor)75.5% ↗not reported——
Chartography (no tools)61.6% ↗not reported——
CursorBench 4.055.5% ↗not reported——
FrontierCode v1.1 (Main)46.2% ↗not reported——
FrontierMath Tier 4 v2 (Epoch AI run)80.5% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)88.8% ↗epoch runnot reported——
FrontierSWE V2 (Proximal Labs)61.9% ↗not reported——
Furniture Assembly (Epoch AI run)75% ↗epoch runnot reported——
Humanity's Last Exam (with tools)64.5% ↗not reported——
LiveBench Agentic Coding (LiveBench)56.3% ↗not reported——
LiveBench Coding (LiveBench)91.4% ↗not reported——
LiveBench Data Analysis (LiveBench)78.6% ↗not reported——
LiveBench Instruction Following (LiveBench)70.5% ↗not reported——
LiveBench Language (LiveBench)83.4% ↗not reported——
LiveBench Mathematics (LiveBench)96.7% ↗not reported——
LiveBench Reasoning (LiveBench)91.6% ↗not reported——
LMArena Agent (LMArena)0.1252 ↗not reported——
LMArena Vision (LMArena)1268.3 ↗not reported——
LMArena WebDev (LMArena)1786.3 ↗not reported——
Mystery Game Puzzles (Epoch AI run)65% ↗epoch runnot reported——
OSWorld 2.1 (partial)80.1% ↗not reported——
SAGE (Vals AI)51.8% ↗not reported——
SimpleBench (SimpleBench)75.9% ↗not reported——
SimpleQA Verified46.5% ↗epoch runnot reported——
Terminal-Bench 4.070.6% ↗not reported——
Terminal-Bench 4.0 (Vals AI)64.1% ↗not reported——
Only Seed-OSS-36B-Instruct reports · 16
MMLUnot reported87.4% ↗——
MMLU-Pronot reported82.7% ↗——
AIME24not reported91.7% ↗——
AIME25not reported84.7% ↗——
BeyondAIMEnot reported65% ↗——
Chess Puzzles (Epoch AI run)not reported13% ↗epoch run——
GPQA-Dnot reported71.4% ↗——
HLEnot reported10.1% ↗——
IFEvalnot reported85.8% ↗——
LiveCodeBench v6 (02/2025-05/2025)not reported67.4% ↗——
MMMLUnot reported78.4% ↗——
Multi-SWE-Benchnot reported17% ↗——
RULER (128K)not reported94.6% ↗——
SuperGPQAnot reported55.7% ↗——
SWE-Bench Verified (OpenHands)not reported56% ↗——
TAU1-Retailnot reported70.4% ↗——
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 Sonnet 5.5 minus Seed-OSS-36B-Instruct 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 Sonnet 5.5Seed-OSS-36B-InstructEdge
Context window1M tokens512K tokensClaude Sonnet 5.5
Max output128K tokens——
Input price / 1M$2 ↗——
Output price / 1M$10 ↗——
Cached input / 1M$0.2 ↗——
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$12——
Modalitiestext · visiontextClaude Sonnet 5.5
Released2026-09-282025-08-20—
Cited benchmark scores2918—
Reliability

Provider status

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