Gemini 3.1 Flash-Lite vs Kimi K3
Google's Gemini 3.1 Flash-Lite and Moonshot AI's Kimi K3 both target production language workloads, but they price and behave differently. Here is the side-by-side.
Pricing checked against provider documentation on . How we verify
The short answer
Gemini 3.1 Flash-Lite is the cheaper option — roughly 10.7x less on a blended workload, and it suits ultra-cheap high-volume tasks. Kimi K3 justifies its premium when you need natively multimodal long-horizon agents. Only Kimi K3 does native reasoning, which matters for multi-step tasks but adds billable thinking tokens.
Google • Gemini 3.1
$0.25 / $1.50
/ 1M tokens (input / output)
Google's efficiency tier and a long-term stable target, priced for workloads measured in millions of calls rather than thousands. It gives up the deeper reasoning of 3.5 Flash, so it suits mechanical tasks — classification, extraction, moderation — where a million tokens of context still helps but chain-of-thought does not.
Moonshot AI • Kimi K
$3.00 / $15.00
/ 1M tokens (input / output)
At 2.8T total parameters with 104B active, Kimi K3 is the largest open-weight model in general circulation and the only one here that ingests video natively. Reasoning is always on with configurable effort. The licence is the catch: it is not a standard open licence, and organisations above $20M in revenue need a separate commercial agreement.
Input price
Kimi K3 is 12.0x the price than Gemini 3.1 Flash-Lite on input tokens.
Output price
Kimi K3 is 10.0x the price than Gemini 3.1 Flash-Lite on output tokens — usually the side that dominates the bill.
Monthly cost at three workload sizes
Standard (non-batch, non-cached) rates. Reasoning models will exceed these figures because thinking tokens bill as output.
| Workload | Gemini 3.1 Flash-Lite | Kimi K3 | Difference |
|---|---|---|---|
| Light — 1M in / 200K out | $1 | $6 | $5 |
| Moderate — 10M in / 2M out | $6 | $60 | $55 |
| Heavy — 100M in / 20M out | $55 | $600 | $545 |
Specification comparison
| Attribute | Gemini 3.1 Flash-Lite | Kimi K3 |
|---|---|---|
| Input (/ 1M tokens) | $0.25 | $3.00 |
| Output (/ 1M tokens) | $1.50 | $15.00 |
| Cached input | — | $0.30 |
| Context window | 1,048,576 tokens | 1,048,576 tokens |
| Max output | 65,536 tokens | 131,072 tokens |
| Native reasoning | No | Yes |
| Knowledge cutoff | 2025-01 | 2026-02 |
| Relative latency | low | high |
| Open weights | No | Kimi K3 License (commercial terms above $20M revenue) |
| API model ID | gemini-3.1-flash-lite | kimi-k3 |
| Status | stable | stable |
Kimi K3: The custom licence requires a separate commercial agreement once the licensee and its affiliates exceed $20M revenue over any consecutive 12 months.
Choose Gemini 3.1 Flash-Lite if…
- Content moderation at volume
- Classification and routing
- Lightweight summarization
- Cheap long-context retrieval
Choose Kimi K3 if…
- Multimodal agent workflows
- Video and image understanding at length
- Ambitious long-horizon automation
- Research requiring open weights at scale
Frequently asked
Is Gemini 3.1 Flash-Lite or Kimi K3 cheaper?
Gemini 3.1 Flash-Lite is cheaper. On a blended 3:1 input-to-output workload it costs about 10.7x less than Kimi K3.
Which has the larger context window, Gemini 3.1 Flash-Lite or Kimi K3?
Both accept up to 1.05M tokens, so context is not a differentiator here.
Should I use Gemini 3.1 Flash-Lite or Kimi K3?
Pick Gemini 3.1 Flash-Lite for ultra-cheap high-volume tasks. Pick Kimi K3 for natively multimodal long-horizon agents. If cost dominates the decision, Gemini 3.1 Flash-Lite wins; if you need the capability ceiling, benchmark both on your own evals before committing.