Gemini 3.1 Flash Lite is $1.75 cheaper per 1M input tokens (87.5% lower; 8x difference).
API cost decision in 10 seconds
Grok 4.5 vs Gemini 3.1 Flash Lite
Pick Gemini 3.1 Flash Lite when budget and context both matter.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Gemini 3.1 Flash Lite when budget and context both matter.
On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite is estimated at $1 vs $5 for Grok 4.5, saving $4 (80% lower).
Cost-first pickGemini 3.1 Flash Lite
Context-first pickGemini 3.1 Flash Lite
Sample savings$480%
10x traffic gap$40
Gemini 3.1 Flash Lite is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $40. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Gemini 3.1 Flash Lite stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Grok 4.5 | Gemini 3.1 Flash Lite |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Gemini 3.1 Flash Lite | $13 | $2 |
| Balanced workload | 1M input + 1M output | Gemini 3.1 Flash Lite | $8 | $1.75 |
| Output-heavy chatbot | 1M input + 5M output | Gemini 3.1 Flash Lite | $32 | $7.75 |
Gemini 3.1 Flash Lite is $4.5 cheaper per 1M output tokens (75% lower; 4x difference).
Gemini 3.1 Flash Lite has 548.58K more context (2.1x larger).
Gemini 3.1 Flash Lite is $4 cheaper on the standard workload (80% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Gemini 3.1 Flash Lite has the lower input price; Gemini 3.1 Flash Lite has the lower output price; Gemini 3.1 Flash Lite offers the larger context window. For the 1M input plus 500K output sample, Gemini 3.1 Flash Lite is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $5 for Grok 4.5 and $1 for Gemini 3.1 Flash Lite.
Choose Grok 4.5 when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
Choose Gemini 3.1 Flash Lite when you care most about lower input-token price, lower output-token price, and larger context window.
- On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite is estimated at $1 vs $5 for Grok 4.5, saving $4 (80% lower).
- Gemini 3.1 Flash Lite is $4 cheaper on the standard workload (80% lower).
- Gemini 3.1 Flash Lite is $1.75 cheaper per 1M input tokens (87.5% lower; 8x difference).
- Gemini 3.1 Flash Lite is $4.5 cheaper per 1M output tokens (75% lower; 4x difference).
- Gemini 3.1 Flash Lite has 548.58K more context (2.1x larger).
| Feature | Grok 4.5 (SpaceXAI) | Gemini 3.1 Flash Lite (Google) |
|---|---|---|
| Input Price prompt tokens per 1M | $2 | $0.25 |
| Completion Price per 1M tokens | $6 | $1.5 |
| Sample Workload Cost 1M input + 500K output | $5 | $1 |
| Context Window | 500K | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Gemini 3.1 Flash Lite | On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite is estimated at $1 vs $5 for Grok 4.5, saving $4 (80% lower). |
| High-volume input processing | Gemini 3.1 Flash Lite | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Gemini 3.1 Flash Lite | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Gemini 3.1 Flash Lite | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Grok Build 0.1 can replace Grok 4.5 when lower sample workload cost matters most: $2.
- Grok 4.3 can replace Grok 4.5 when lower sample workload cost matters most: $2.5.
- Grok 4.20 Multi-Agent can replace Grok 4.5 when lower sample workload cost matters most: $2.5.
- Grok 4.20 can replace Grok 4.5 when lower sample workload cost matters most: $2.5.
- Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- DeepSeek V4 Flash 0731 offers 1.31M context with $0.17 sample workload cost.
- DeepSeek V4 Flash Latest offers 1.31M context with $0.11 sample workload cost.
- DeepSeek V4 Flash 0731 · DeepSeek · #1
- MiMo-V2.5 · Xiaomi · #2
- Hy3 · Tencent · #3
- Ox Alpha · stealth · #4
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Open Google modelsGrok 4.5 is a model from SpaceXAI with frontier performance on coding, knowledge work, and STEM.
Gemini 3.1 Flash Lite is Google’s GA high-efficiency multimodal model optimized for low-latency, high-volume workloads. It supports text, image, video, audio, and PDF inputs, and is designed for lightweight agentic...