Model

Seed 2.1 Pro

CLOSED

ByteDance · Doubao Seed family · released Jun 24, 2026

ByteDance's newest flagship (successor to Seed 2.0 Pro from Feb 2026), positioned by ByteDance as competitive with Claude Opus 4.6 at far lower cost; not in corpus (corpus's newest ByteDance entry is Doubao-Seed-1.6 from 2025-06-11). Pricing converted from RMB (6/30 per million input/output) at ~7.1 RMB/USD.

ReasoningCodingVisionFunction callingTool useAgentic

2665.9

Elo · rank #9

Parameters

Undisclosed

Active params

—

Context

256K tokens

Architecture

Proprietary deep-thinking agent model, architecture undisclosed

License

Proprietary

Languages

—

API price (in/out)

$0.85 / $4.15

Modalities

text · vision

Benchmark results

Bar shows position within the tracked field; marker = field best

Agents' Last ExamAgents41.4%#7

best: GPT-5.6 · 52.7%

ARC-AGI-2Reasoning62.5%#9

best: GPT-5.6 · 92.5%

BrowseCompAgents86.2%#4

best: Kimi K3 · 91.2%

CharXivVision85.4%#3

best: Muse Spark 1.1 (xhigh) · 88.4%

GDPvalAgents87.9%#1

best: this model · 87.9%

Humanity's Last ExamReasoning42.9%#19

best: Claude Sonnet 5 · 57.4%

MathVisionVision92.6%#1

best: this model · 92.6%

MathVistaVision90.7%#1

best: this model · 90.7%

MMMU-ProVision81.6%#4

best: Claude Opus 4.7 · 85.5%

OSWorldAgents78.8%#1

best: this model · 78.8%

SuperGPQAReasoning70.8%#4

best: Qwen3.7-Max · 73.6%

Terminal-Bench 2.0Coding71.0%#14

best: GPT-5.6 · 88.8%

Video-MMEVision89.2%#1

best: this model · 89.2%

Run it locally

Closed weights — available via API only. No local deployment.

Input / M tok

$0.85

Output / M tok

$4.15

Doubao Seed family

Elo progression across releases

Seed 2.1 ProJun 20262665.9

Resources

DOCShttps://seed.bytedance.com/en/seed2_1 APIAvailable via ByteDance API

API price $0.85/$4.15 · each benchmark row carries its own source badge (see methodology)