Kimi K3 · Writing
Kimi K3 for writing: our test runs
Kimi K3 ran our 5 writing prompts in llmwise, through the same pipeline your messages take. Here's every reply as it came, whether it passed, what it cost and what it counts as on Pro, next to the other models.
Based on 5 of our test runs on , through OpenRouter with the app's own prompt and settings.
Short answer
In our test runs on September 27, 2026, Kimi K3 passed 4 of 5 of our writing prompts (1 of the 2 hard ones): tied 3rd of 15 models. Each reply counted as 1 message on Pro, where it has 125 a month, and cost $0.0038 to run on average.
Prompt by prompt
Each of the 5 writing prompts, and how Kimi K3's reply did.
| Prompt | Result | Cost | Time |
|---|---|---|---|
| Announce a second bakery shop on LinkedInEveryday | Passed: Graded 4.5 of 5 on average (lowest 4). | $0.0046 | 3.9 s |
| Rewrite corporate jargon in plain wordsEveryday | Passed: Graded 4.3 of 5 on average (lowest 4). | $0.0030 | 2.0 s |
| Decline a meeting and offer two timesEveryday | Passed: Graded 5.0 of 5 on average (lowest 5). | $0.0034 | 3.0 s |
| A product announcement with five rulesHard | Failed: Graded 4.3 of 5 on average (lowest 4); but doesn't end with a question. | $0.0033 | 2.3 s |
| Argue both sides of free busesHard | Passed: Graded 4.7 of 5 on average (lowest 4). | $0.0049 | 3.6 s |
Every writing reply from Kimi K3
Announce a second bakery shop on LinkedIn
An everyday prompt: “Announce a second bakery shop on LinkedIn”, in full.
Passed: Graded 4.5 of 5 on average (lowest 4).
Big news from Crumb & Co. — we're opening our second shop in Leeds on 14 November! When we started this little bakery, we never imagined we'd grow beyond our first shop. But thanks to everyone who's queued for our sourdough, recommended us to a friend, or simply popped in for a chat and a cinnamon bun, here we are. A second home, a new neighbourhood, and a lot of excitement (and a little nervousness) on our side. To say thank you, we'll be handing out free coffee all day on opening day. Come along, grab a cup, try something fresh from the oven, and say hello — we'd love to meet our new neighbours. Same recipes, same care, same friendly faces (plus a few new ones). Just a new postcode. Doors open 14 November. We can't wait to see you there. — The Crumb & Co. team
476 tokens in, 210 out (14 of them reasoning) · 3.9 s · $0.0046 · 1 message on Pro · answered by moonshotai/kimi-k3 via Together ·
Rewrite corporate jargon in plain words
An everyday prompt: “Rewrite corporate jargon in plain words”, in full.
Passed: Graded 4.3 of 5 on average (lowest 4).
In Q3, teams across the company worked together to focus more on customers. As a result, customer retention improved by 12%, and the rate at which enterprise customers left dropped by 30 basis points (0.3%). We also streamlined our communication channels—such as phone, email, and online—to use our time and resources more efficiently.
504 tokens in, 120 out (38 of them reasoning) · 2.0 s · $0.0030 · 1 message on Pro · answered by moonshotai/kimi-k3 via Together ·
Decline a meeting and offer two times
An everyday prompt: “Decline a meeting and offer two times”, in full.
Passed: Graded 5.0 of 5 on average (lowest 5).
Subject: Re: Vendor Demo Invitation Hi Tom, Thanks for the invitation to the vendor demo on Wednesday at 11:00. Unfortunately, I'll be presenting to the board at that time and won't be able to attend. Would either Thursday at 10:00 or Friday at 14:00 work instead? I'm happy to reschedule if neither suits you. Thanks for understanding, and I look forward to the demo. Best regards, [Your Name]
484 tokens in, 108 out (4 of them reasoning) · 3.0 s · $0.0034 · 1 message on Pro · answered by moonshotai/kimi-k3 via Fireworks ·
A product announcement with five rules
A hard prompt: “A product announcement with five rules”, in full.
Failed: Graded 4.3 of 5 on average (lowest 4); but doesn't end with a question.
**Introducing the Nordvik 2 Desk Lamp** Meet the Nordvik 2, our redesigned desk lamp built for focused work and relaxed evenings. Fine-tune your lighting with five-step dimming, and enjoy the flexibility of an arm that rotates a full 270 degrees to direct light exactly where you need it. Charging is simple via USB-C, so it fits seamlessly into any modern workspace. The Nordvik 2 is available for €79 and ships on 1 December. Ready to see your desk in a better light? (59 words)
493 tokens in, 145 out (22 of them reasoning) · 2.3 s · $0.0033 · 1 message on Pro · answered by moonshotai/kimi-k3 via Together ·
Argue both sides of free buses
A hard prompt: “Argue both sides of free buses”, in full.
Passed: Graded 4.7 of 5 on average (lowest 4).
Free buses would transform urban life. Fares raise little revenue after collection costs, yet they deter the very riders—low-income workers, students, the elderly—who depend on transit most. Eliminating them speeds boarding, cuts traffic congestion, reduces emissions, and functions as targeted economic relief for households struggling with costs. Cities like Tallinn and Kansas City show ridership climbs sharply when fares vanish. A city that wants cleaner air, less gridlock, and genuine mobility equity should treat buses like libraries or parks: a public good, free at the point of use. Yet "free" transit is never free—someone pays, and often it's riders themselves. Forgoing fare revenue means cutting service frequency, deferring maintenance, or raising taxes on residents who never ride. Crowded, deteriorating buses push people back into cars, worsening congestion. Studies show riders value reliability far more than zero fares; a bus that comes every five minutes beats a free one that comes hourly. Scarce funds spent subsidizing middle-class commuters could instead expand routes to underserved neighborhoods. Better to invest in service quality than in a populist gesture.
471 tokens in, 248 out (11 of them reasoning) · 3.6 s · $0.0049 · 1 message on Pro · answered by moonshotai/kimi-k3 via Together ·
How it compares on writing
Kimi K3 beside the job's picks among every model. 2 models share the hard-problems pick, and Kimi K3 isn't one of them.
| Model | Passed | On Pro | Cost per reply |
|---|---|---|---|
| GLM 5.3Our pick: best value | 4 of 5 | 250 a month on Pro | $0.0006 |
| GPT-6 LunaOur pick: hard problems (shared), everyday | 5 of 5 | 60 a day on Pro | $0.0001 |
| Kimi K3 | 4 of 5 | 125 a month on Pro | $0.0038 |
Every limit is published. Paid plans also have a monthly fair-use limit on AI cost: Pro $7.50, Max $20, Ultra $42, Studio $85. Using every message on your plan at typical sizes stays under it; very large messages and heavy research use it faster. Every limit, explained.
How these runs were done
Rubric (graded). The grader model scores the reply from 1 to 5 on each published criterion. It passes with an average of 4 or more and no criterion under 3, and only if it also meets the prompt's automatic rules (length, words it must or mustn't use).
The grader is Claude Opus 5.5 at low reasoning effort; its own replies are graded by GPT-6 Astra, so no model grades itself. Its prompt and every rubric are on the methods page.
Kimi K3, and writing, elsewhere
- Kimi K3: price, limits and messages on every plan
- The best AI for writing: our picks among every model
- Kimi K3 for coding: our test runs
- Kimi K3 for math: our test runs
- Kimi K3 for data analysis: our test runs
- Claude Fable 5.1 vs Kimi K3
- Rewrite for clarity: the prompt, and its price on each model
- Our test runs: 50 prompts on every model
Questions
Is Kimi K3 good for writing?
In our test runs it passed 4 of 5 writing prompts, tied 3rd of the 15 models in llmwise. Every reply is on this page, so you can judge them yourself.
How many of my messages does a writing reply from Kimi K3 use?
1 message each on Pro, where it has 125 a month on Pro. The price of a message is fixed and shown before you send it, however long the reply.
How were these runs done?
The same way for every model: each prompt sent through llmwise's own pipeline, each reply checked the same way. The methods page has every prompt and how each is scored.
Claude, GPT, Gemini, DeepSeek, Grok, Kimi, and GLM, in one chat.
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