Gemini 3.8 Flash vs Grok 4.6: pricing and benchmarks
Gemini 3.8 Flash is 63% cheaper on input tokens ($0.75 vs $2.00 per 1M). Gemini 3.8 Flash is 38% cheaper on output tokens ($3.75 vs $6.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.8 Flash costs $412.50 a month versus $980.00 for Grok 4.6, 58% less. Roughly tied. Gemini 3.8 Flash scores 156.5 and Grok 4.6 scores 156.3 on the Epoch Capabilities Index, and their confidence intervals overlap.
Prices verified September 14, 2026.
Which should you choose?
Roughly tied. Gemini 3.8 Flash scores 156.5 and Grok 4.6 scores 156.3 on the Epoch Capabilities Index, and their confidence intervals overlap.
Gemini 3.8 Flash scores 73.8% on DeepSWE vs 67.5% for Grok 4.6.
Gemini 3.8 Flash scores 68.4% on FrontierMath (Tiers 1–3) vs 66.0% for Grok 4.6.
Gemini 3.8 Flash costs $1.50 per 1M tokens (3:1 input-to-output mix) vs $3.00 for Grok 4.6, 50% less.
Gemini 3.8 Flash delivers equal or higher overall capability for 50% less.
Pricing and specs
| Gemini 3.8 Flash | Grok 4.6 | |
|---|---|---|
| Provider | xAI | |
| API model ID | gemini-3.8-flash | grok-4.6 |
| Input / 1M tokens | $0.75 | $2.00 |
| Cached input / 1M tokens | $0.075 | $0.50 |
| Output / 1M tokens | $3.75 | $6.00 |
| Long-context rates | — | $4.00 in / $12.00 out above 200K prompt tokens |
| Context window | 1.05M tokens | 500K tokens |
| Max output | 66K tokens | — |
| Batch discount | 50% off | — |
Benchmarks
| Gemini 3.8 Flash | Grok 4.6 | |
|---|---|---|
| Epoch Capabilities Index | 156.5 | 156.3 |
| GPQA Diamond· Science reasoning | 93.9% | 92.0% |
| FrontierMath (Tiers 1–3)· Advanced math | 68.4% | 66.0% |
| SimpleQA Verified· Factual accuracy | 69.7% | 49.3% |
| ARC-AGI-2· Abstract reasoning | — | 67.1% |
| DeepSWE· Coding | 73.8% | 67.5% |
| APEX-Agents· Agentic work | — | 41.2% |
Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks
Monthly cost for real workloads
| Workload | Gemini 3.8 Flash | Grok 4.6 | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $262.50 | $540.00 | Gemini 3.8 Flash 51% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $412.50 | $980.00 | Gemini 3.8 Flash 58% cheaper |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $186.00 | $500.00 | Gemini 3.8 Flash 63% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
Gemini 3.8 Flash vs Grok 4.6 cost calculator
- $412.50/mo$0.0083 / request
- Grok 4.6xAI$980.00/mo$0.02 / request
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
Gemini 3.8 Flash pricing notes
Google’s newest Flash model, with thinking, tool use and a 1M-token context window.
- Introductory price through December 31, 2026. From January 1, 2027: $1.50 input, $0.15 cached, $7.50 output per 1M tokens.
- Output price includes thinking tokens.
- Priority inference costs 1.8x the standard rate.
Grok 4.6 pricing notes
xAI’s flagship model for code and everything else, with agentic tool calling and configurable reasoning.
- Requests with 200K or more prompt tokens are billed at $4 input / $1 cached / $12 output for all tokens.
- Web Search and X Search tools cost $5 per 1,000 calls.
Frequently asked questions
- Is Gemini 3.8 Flash cheaper than Grok 4.6?
- Gemini 3.8 Flash is 63% cheaper on input tokens ($0.75 vs $2.00 per 1M). Gemini 3.8 Flash is 38% cheaper on output tokens ($3.75 vs $6.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.8 Flash costs $412.50 a month versus $980.00 for Grok 4.6, 58% less.
- Which is more capable, Gemini 3.8 Flash or Grok 4.6?
- Roughly tied. Gemini 3.8 Flash scores 156.5 and Grok 4.6 scores 156.3 on the Epoch Capabilities Index, and their confidence intervals overlap.
- How much does Gemini 3.8 Flash cost per 1M tokens?
- Gemini 3.8 Flash costs $0.75 per 1M input tokens and $3.75 per 1M output tokens, and $0.075 per 1M cached input tokens on Google’s standard tier.
- How much does Grok 4.6 cost per 1M tokens?
- Grok 4.6 costs $2.00 per 1M input tokens and $6.00 per 1M output tokens, and $0.50 per 1M cached input tokens on xAI’s standard tier.
- Which has the larger context window, Gemini 3.8 Flash or Grok 4.6?
- Gemini 3.8 Flash has the larger context window: 1.05M tokens versus 500K for Grok 4.6.