AI Model Comparison
Side-by-side comparison of pricing, context window, benchmarks, capabilities, and license. Every figure comes from the developer's own pages, last checked on ; each model's page lists its sources. A figure we could not source shows as a dash.
Model A — Moonshot AI
Kimi K3 is Moonshot AI's 2.8-trillion-parameter open-weight Mixture-of-Experts model with native vision and a 1-million-token context window, built on Kimi Delta Attention and Attention Residuals. On the API it always reasons, with configurable reasoning effort.
Model B — ByteDance Seed
Seed2.1 Pro is the larger model of ByteDance Seed's Seed2.1 family, which ByteDance describes as agent-capable models for real-world productivity, aimed at stronger reasoning, agentic execution and complex workflows. It is available to Doubao and Volcano Engine users as Doubao-Seed-2.1-Pro.
| Property | Kimi K3 | Seed2.1 Pro |
|---|---|---|
| Released | Jul 16, 2026 | Jun 23, 2026 |
| Developer | Moonshot AI | ByteDance Seed |
| Type | multimodal | multimodal |
| License | open-weight | proprietary |
| Context window | 1,048,576 | — |
| Parameters | 2.8T total, 104B activated (MoE; 16 of 896 experts per token) | — |
| Developer status | — | — |
| Input $/M tokens | $3.00 | — |
| Output $/M tokens | $15.00 | — |
Bold green values indicate the winner on that dimension where comparison is meaningful (lower price wins; bigger context wins; more open license wins; newer date wins). Prices are the ones each developer lists today; a model it no longer prices has none.
Programmatic access available at /api/ai/compare?a=kimi-k3&b=seed-2-1-pro. CORS is open. Citation guidance: /about/editorial-process.