OpenAI Codex Mini vs 
Kimi K3
OpenAI Codex Mini is cheaper than Kimi K3 at $1.5/M vs $3/M input tokens.
Pokémon Battle UI Recreation
Pokémon battle screen you can actually click. One HTML file.
Loading the build
Loading the build
Which answer wins?
Written rounds
2 promptsThree minutes of stand-up. Puns are banned.
OpenAI Codex Mini: [Comedian walks onstage] Hey, everyone! Great to see you all tonight. I'm Jamie—if you thought that intro was enthusiastic, you should've seen me when I realized this place has Wi-Fi. Seriously, though, I love stand-up.
Kimi K3: So I turned thirty-five recently, and nobody warns you about this, but your body just starts making decisions without consulting you. I sneezed last week and threw out my back. A sneeze! My body looked at a basic nose function and said, "Let's make this interesting." I was on the floor for twenty minutes.
Five jokes on demand, then count how many were actually different.
OpenAI Codex Mini: Sure—here are five jokes: I asked the librarian if books about paranoia were available. She whispered, "They're right behind you." Why did the tomato turn red? Because it saw the salad dressing. I bought a boat because it was for sail. Don't trust stairs—they're always up to something.
Kimi K3: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything! Why did the scarecrow win an award? Because he was outstanding in his field! Why don't skeletons fight each other? They don't have the guts. What do you call a fish with no eyes? A fsh. Why did the math book look sad?
Price and specs
Not enough votes to call it. On the specs, Kimi K3 has the edge: bigger model tier, newer, bigger context window.
| Spec | OpenAI Codex Mini | Kimi K3 |
|---|---|---|
| Input price | $1.5/M tokens | $3/M tokens |
| Output price | $6/M tokens | $15/M tokens |
| Context window | 200K tokens | 1.0M tokens |
| Weights | — | Open |
| Free API (OpenRouter) | No | No |
| Released | May 2025 | Jul 2026 |
| At 10M a month | $15.00 | $30.00 |
Input tokens at list price. No caching, no batch discount.
Where to run it
OpenAI Codex Mini
No hosts listed on OpenRouter.
Kimi K320 hosts
- Wafer$0.60 in$15.00 out1M100% up
- InferenceNetfp4$0.80 in$13.50 out1M100% up
- Sail Researchfp4$0.84 in$13.50 out1M99.9% up
- AkashMLfp4$1.20 in$14.00 out1M97.6% up
- Morphfp8$1.30 in$14.00 out1M99.8% up
- Makorafp4$1.53 in$12.75 out1M99.6% up
14 more hostsFewer hosts
- Relacefp4$2.00 in$14.00 out1M100% up
- Decartmxfp4$2.55 in$12.75 out1M96.9% up
- Phala$2.55 in$12.75 out1M99.4% up
- DigitalOcean$2.55 in$12.95 out1M100% up
- Parasailfp4$2.60 in$13.00 out1M100% up
- Together$2.70 in$13.50 out1M98.1% up
- DeepInframxfp4$2.85 in$14.25 out1M100% up
- Amazon Bedrock$3.00 in$15.00 out1M98.3% up
- Basetenfp8$3.00 in$15.00 out1M100% up
- Chutesmxfp4$3.00 in$15.00 out1M90.9% up
- Fireworks$3.00 in$15.00 out1M100% up
- Modalmxfp4$3.00 in$15.00 out1M100% up
- Moonshot AImxfp4$3.00 in$15.00 out1M100% up
- Alibaba Cloud$3.45 in$17.25 out1M100% up
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Common questions
What is the difference between OpenAI Codex Mini and Kimi K3?
OpenAI Codex Mini is developed by OpenAI while Kimi K3 is developed by Moonshot AI. OpenAI Codex Mini has a 200K token context window vs Kimi K3's 1.0M. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.
Which is better, OpenAI Codex Mini or Kimi K3?
It depends on your use case. OpenAI Codex Mini and Kimi K3 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 10 challenges so you can judge which fits your needs best.
How much does OpenAI Codex Mini cost compared to Kimi K3?
OpenAI Codex Mini costs $1.5/M input tokens and Kimi K3 costs $3/M input tokens. OpenAI Codex Mini is $1.50/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
How can I compare OpenAI Codex Mini and Kimi K3 on Rival?
This page shows a side-by-side comparison of OpenAI Codex Mini and Kimi K3 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.
More comparisons
Against the newest arrivals
- OpenAI Codex Mini vs Step 5 PreviewLanded Oct 2026
- Kimi K3 vs Claude Haiku 5.5Landed Oct 2026
- OpenAI Codex Mini vs Ling 3.1 FlashLanded Oct 2026
- Kimi K3 vs Mistral Large 4Landed Oct 2026
- OpenAI Codex Mini vs GPT-6.1 SolLanded Sep 2026
- Kimi K3 vs Claude Sonnet 5.5Landed Sep 2026
- OpenAI Codex Mini vs Solar Mini 4Landed Sep 2026
- Kimi K3 vs Qwen3.8 Max PrimeLanded Sep 2026
