TL;DR
- Kimi K3.1 Pro Highspeed (
kimi-k3.1-pro-highspeed) is a speed-tier variant of Pro: 2x the price for 3x the response speed (official figure). Protocol and parameters are identical to Pro. - Platform pricing: input $4.3096 / output $22.5426 / cached read $0.2156 per million tokens. A single 2K-input + 1K-output request costs roughly $0.031.
- Available now on HiAPI. Open the model page to try it. New users get 200 free credits.
Kimi K3.1 Pro Highspeed vs Pro: What the Price Gap Buys You
Highspeed is not a different model. It is Pro, served through a faster inference pipeline. Moonshot AI added a speed-tier line that delivers 3x the response speed at 2x the price. For API callers, the only difference from Pro is: a different model ID, a bill that is twice as high, and wait times that are cut by roughly two-thirds.
| Item | kimi-k3.1-pro | kimi-k3.1-pro-highspeed | Difference |
|---|---|---|---|
| Input $/M | $2.1548 | $4.3096 | 2x |
| Output $/M | $11.2714 | $22.5426 | 2x |
| Cached read $/M | $0.2156 | $0.2156 | Same |
| Response speed | Baseline | 3x | — |
| Protocol | Chat Completions | Chat Completions | Identical |
| Parameters | 9 | 9 | Identical |
HiAPI live pricing, verified October 2026. All prices in USD per million tokens.
Cached reads cost the same on both tiers at $0.2156. If you keep your system prompt and background context fixed at the front, repeated requests that hit the cache effectively sidestep the speed premium on that portion.
What Your Usage Actually Costs
Per-request cost. 2K input + 1K output: roughly $0.0086 + $0.0225 = $0.031. The same request on Pro costs about $0.016. The extra $0.015 buys 3x response speed.
How far $10 goes. At a moderate 1K-input + 3K-output request size (~$0.072 per call), $10 gets you roughly 139 requests. The same $10 on Pro would cover about 278. Choosing Highspeed means trading throughput for responsiveness.
Monthly budget matrix.
| Volume | Per-request cost | Monthly (30 days) |
|---|---|---|
| 10 moderate requests/day | $0.072 | ~$22 |
| 100 moderate requests/day | $0.072 | ~$216 |
| 1,000 moderate requests/day | $0.072 | ~$2,160 |
At high volume, the difference adds up fast. At 100 requests per day, Highspeed runs about $216/month versus $108/month on Pro. Make sure the speed is actually worth it for your use case.
When to Choose Highspeed vs Pro
| Scenario | Recommendation | Why |
|---|---|---|
| Chatbots, live customer support | Highspeed | Users are waiting; time-to-first-token defines the experience |
| Real-time code completion | Highspeed | Millisecond differences are perceptible inside an IDE |
| Batch text processing, offline labeling | Pro | Latency does not matter; halve your costs first |
| Agent loops (multi-turn tool calls) | Depends on budget | Per-turn cost doubles, but accumulated latency savings can be significant |
| Translation, summarization (long outputs) | Pro | Output tokens dominate the bill at 2x price; latency gains are diluted by output length |
The rule of thumb: user is waiting = Highspeed; background processing = Pro.
How to Spend Less
- Cache your system prompts. Cached reads at $0.2156 are the same price as Pro. Keep system prompts fixed at the front; repeated requests hitting the cache skip the speed premium on that portion.
- Set reasoning_effort explicitly. Three levels: low / high / max (default max). Drop to low for simple tasks; output tokens and inference time drop together.
- Cap output with max_tokens. Output is $22.5426/M, double Pro. Unbounded long outputs can inflate bills quickly.
Competitive Pricing Snapshot
| Model | Input $/M | Output $/M | Cached Read $/M | Notes |
|---|---|---|---|---|
| kimi-k3.1-pro-highspeed | $4.3096 | $22.5426 | $0.2156 | 3x speed, 2x price of Pro |
| kimi-k3.1-pro | $2.1548 | $11.2714 | $0.2156 | Baseline |
| kimi-k3 | $2.32 | $11.60 | $0.232 | Previous generation |
| claude-opus-5-5 | $2.02 | $10.08 | $0.10 | 1M context |
HiAPI live pricing, verified October 2026.
Highspeed output pricing sits noticeably above others in this bracket. That is the speed premium. If your workload does not demand ultra-low latency, Pro or claude-opus-5-5 offer better cost efficiency.
FAQ
Are Kimi K3.1 Pro Highspeed and Pro the same model? Yes. Capabilities and parameters are identical. The only differences are response speed and price. Highspeed is Pro running on a faster inference pipeline.
When should I use Highspeed? When users are waiting: chatbots, customer support, code completion, real-time search. For background processing and offline tasks, Pro is sufficient.
Is cached read really the same price as Pro? Yes, $0.2156/M on both. Heavy users running repeated calls with fixed system prompts benefit the most: cache hits skip the input charge entirely on that portion.
Do I need to change my code?
Not at all. Same Chat Completions protocol, same parameters. Change the model ID from kimi-k3.1-pro to kimi-k3.1-pro-highspeed and you are done. See the API guide for full examples.
Decide whether your workload is latency-sensitive or cost-sensitive first. If users are waiting, open the model page and send a test request. New users get 200 credits; your first trial is essentially free.
