Kimi K3 vs GPT-6.1 Sol: API price, context and cost per task
Kimi K3 against GPT-6.1 Sol: open weights and a fluctuating price versus OpenAI's high-end model with fixed list rates.
On output, GPT-6.1 Sol is 1.6x cheaper ($10 vs $16 per million tokens). On input, Kimi K3 is 10x cheaper ($0.192 vs $2 per million tokens). GPT-6.1 Sol reads more per request: 1,050,000 tokens against 1,048,576.
Data updated 2026-11-12 - source: public OpenRouter model list, refreshed daily. Prices in USD, excluding VAT.
Specs and prices side by side
| Kimi K3 | GPT-6.1 Sol | |
|---|---|---|
| Vendor | Moonshot AI | OpenAI |
| Input, per 1M tokens | $0.192 | $2 |
| Output, per 1M tokens | $16 | $10 |
| Cached input, per 1M | $0.182 | $0.1 |
| Batch (input / output) | $2.28 / $11.4 | $1 / $5 |
| Context window | 1,048,576 | 1,050,000 |
| Max output | 943,718 | 128,000 |
| Input types | text, images, video | text, images, files |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| On OpenRouter since | 16 Jul 2026 | 29 Sep 2026 |
Highlighted: the cheaper price or the larger limit. "Not published" means the figure is not in the public model listing yet.
What a month of work costs
Four typical workloads at today's list prices. Reasoning models also bill their thinking as output tokens, so treat output-heavy numbers as a floor.
| Workload | Kimi K3 | GPT-6.1 Sol | Difference |
|---|---|---|---|
| Support chatbot10,000 conversations a month, about 1,500 input and 400 output tokens each | $66.88 | $70 | Kimi K3 1x cheaper |
| Coding agent300 tasks a month, about 80,000 input tokens (code context re-read across steps) and 8,000 output tokens each | $43.01 | $72 | Kimi K3 1.7x cheaper |
| Coding agent with caching70% of input served from the prompt cache | $42.84 | $40.08 | |
| Long-document analysis1,000 documents a month, about 50,000 tokens in and a 1,500-token summary out | $33.60 | $115 | Kimi K3 3.4x cheaper |
| Content drafting600 articles a month, about 3,000 tokens of brief in and 2,500 tokens of draft out | $24.35 | $18.60 | GPT-6.1 Sol 1.3x cheaper |
Price stability over the last 30 days
- Kimi K3: 14 price changes since 13 Oct 2026. Input ranged $0.159 - $0.73, output $10 - $20 per million tokens. Volatile: the listed price follows whichever provider OpenRouter currently routes to, so budget with the upper end of the range.
- GPT-6.1 Sol: no change in the last 30 days.
Kimi K3: price log
| Date | Input | Output |
|---|---|---|
| 2026-11-05 | $0.192 | $16 |
| 2026-11-04 | $0.2 | $16 |
| 2026-10-30 | $0.192 | $15 |
| 2026-10-29 | $0.192 | $20 |
| 2026-10-28 | $0.159 | $20 |
| 2026-10-27 | $0.2 | $20 |
| 2026-10-26 | $0.18 | $16 |
| 2026-10-24 | $0.239 | $10.8 |
What the vendors and benchmarks say
Kimi K3
"Kimi K3 is a 2.8T parameter open-weight multimodal reasoning model from Moonshot AI."model card on OpenRouter
- Open weights: you can run it on your own hardware instead of paying per token. Source: Moonshot AI
- First place in Frontend Code Arena (1679 points) in summer 2026 voting. Source: arena.ai
- 50.9% on the AA-Omniscience hallucination test (lower is better). Source: Artificial Analysis
GPT-6.1 Sol
"GPT-6.1 Sol is an upgrade to GPT-6 Sol from OpenAI, positioned below the flagship GPT-6 Astra in the GPT-6 series."model card on OpenRouter
- Listed on OpenRouter on 29 September 2026, one week after GPT-6 Sol, which it upgrades. Source: OpenRouter
Which one to pick
Check the 30-day range above before budgeting with Kimi K3 - its OpenRouter rate has moved a lot as providers changed. K3 takes video input and has a very large output limit; Sol takes files and images and has a stable price. For predictable production costs Sol is easier; for experiments, frontend work and self-hosting, K3.
Cheaper models with a similar context window
Models from our comparison set that cost less than both on a blended basis and support tool calling. They are not equivalent in quality - test before switching.
- Qwen3.8 Max (Alibaba (Qwen)): $2 / $6 per million tokens, 1M context
- Gemini 3.8 Flash (Google): $0.825 / $4.13 per million tokens, 1.05M context
- DeepSeek V4 Pro (DeepSeek): $0.955 / $1.91 per million tokens, 1.05M context
Related reading
- Kimi K3: input unchanged, output +3%. New rate: 0.30 / 11.94 dollars per million tokens
- Kimi K3: input -20%, output unchanged. New rate: 0.24 / 11.94 dollars per million tokens
- Kimi K3 API price cut: input tokens now $0.45 per million
- Gemini 4 Carbon test: 50+ tasks vs Argon, Claude Fable 5.2 and GPT-6.1 Sol
- Claude Fable 5.2 vs GPT-6.1 Sol vs Gemini 4 Argon: Price, Benchmarks
- GPT-6.1 Terra vs Claude Sonnet 5.5: Polish Test Results
How we calculate
Prices are the public per-token list rates from OpenRouter's model list, which match the vendors' own API prices for first-party models and show the current routed price for open-weight models served by several hosts. Monthly costs multiply those rates by the token volumes in each workload; caching assumes the stated share of input is billed at the cached-input rate. Benchmarks and claims are quoted from the named sources, mostly the vendors themselves - treat them as a guide and test on your own tasks. See also the AI cost calculator and all tracked model prices.
Frequently asked questions
Which is cheaper, Kimi K3 or GPT-6.1 Sol?
As of 12 Nov 2026, Kimi K3 costs $0.192 per million input tokens and $16 per million output tokens; GPT-6.1 Sol costs $2 and $10. Kimi K3 is cheaper in 3 of the 4 monthly workloads we price on this page. The real bill also depends on how many reasoning tokens each model writes.
Which has the larger context window?
Kimi K3 reads up to 1,048,576 tokens and can write up to 943,718; GPT-6.1 Sol reads up to 1,050,000 and writes up to 128,000.
How much does a support chatbot cost on each model?
For 10,000 conversations a month (about 15 million input and 4 million output tokens) you would pay about $66.88 on Kimi K3 and $70 on GPT-6.1 Sol at list prices, before any caching or batch discounts.
Do they offer prompt caching or batch discounts?
Kimi K3 lists cached input at $0.182 per million and a batch rate of $2.28 / $11.4. GPT-6.1 Sol lists cached input at $0.1 per million and a batch rate of $1 / $5. Caching matters most for agents and chatbots that resend the same context on every turn.
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