Kimi K3 Open vs 
GPT-5.5 Paid
Kimi K3 vs GPT-5.5 compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.
Prices & specs refreshed from live data · OpenSourceAI.tech
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
Kimi K3 vs GPT-5.5 specs
| Spec | Kimi K3 | GPT-5.5 |
|---|---|---|
| Maker | Moonshot AI | OpenAI |
| Type | Open-weight | Proprietary |
| Context window | 1M tokens | 1.1M tokens |
| Input price | $3/M · free self-host | $5/M |
| Output price | $15/M · free self-host | $30/M |
| Vision / multimodal | Yes | Yes |
| Tool / function calling | Yes | Yes |
| Self-hostable | Yes | No (API only) |
| License | Modified MIT | Proprietary |
Feature comparison
| Capability | Kimi K3 | GPT-5.5 |
|---|---|---|
| Open weights (downloadable) | ✓ | ✗ |
| Self-hostable | ✓ | ✗ |
| Runs fully offline | ✓ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✓ |
Benchmarks: Kimi K3 vs GPT-5.5
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How Kimi K3 and GPT-5.5 score
| Criterion | Kimi K3 | GPT-5.5 |
|---|---|---|
| Cost-efficiency | 3.0 | 3.0 |
| Context window | 5.0 | 5.0 |
| Openness | 5.0 | 1.5 |
| Self-hosting | 5.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
Kimi K3 Open
Kimi K3 is a 2.8T parameter open-weight multimodal reasoning model from Moonshot AI. It is suited for complex coding, knowledge work, and long-horizon agentic workflows, and is particularly strong at...
GPT-5.5 Paid
GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
Is Kimi K3 as good as GPT-5.5?
Kimi K3 is open-weight and competitive on many tasks, but GPT-5.5 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.
Can I run Kimi K3 locally?
Yes. Kimi K3 has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. GPT-5.5 is API-only and cannot be self-hosted.
How much cheaper is Kimi K3?
Kimi K3 costs $15/M output vs $30/M for GPT-5.5 — roughly 2x cheaper via API, and free if you self-host.
Kimi K3 vs GPT-5.5 — which should I pick in 2026?
Choose Kimi K3 if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose GPT-5.5 if you want frontier capability through a managed API with zero infrastructure to run.
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