GPT-6 Astra vs Gemini 3.1 Pro
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
by OpenAI
|
by Google
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current flagship |
| Released | ||
| Pricing per million tokens | ||
| Input | $10.00/Mtok | $2.00/Mtok |
| Output | $50.00/Mtok | $12.00/Mtok |
| Blended avg | $20.00/Mtok | $4.50/Mtok |
| Cached input | $1.00/Mtok | $0.200/Mtok |
| Price basis | OpenAI's rate card prices this model by context length: the tracked figure is the short-context tier, and prompts over 272K input tokens bill at the long-context tier of $20 input / $2 cached input / $25 cache write / $75 output per 1M tokens — 2x input and cache rates and 1.5x output, applied to the full request. Cache writes bill at 1.25x the uncached input rate. Batch and Flex are 50% of Standard; Fast mode is 2x the applicable rate, and Fast is unavailable with EU data residency. | — |
| Specifications | ||
| Context window | 1M tokens | 2M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimageaudiovideo
|
| Benchmarks source: Vellum LLM Leaderboard | ||
| Avg benchmark score | 96 | 74.8 |
| Perf / dollar | 4.8 | 16.6 |
| GPQA Diamond | 96 | 94.3 |
| Terminal-Bench 2.1 | — | 70.3 |
| MCP Atlas | — | 69.2 |
| BrowseComp | — | 85.9 |
| OSWorld-Verified | — | 76.2 |
| Humanity's Last Exam | — | 44.4 |
| ARC-AGI 2 | — | 77.1 |
| HumanEval | — | 80.6 |
| AutoBench | 41.4 | — |
| Independent composite scores each on its own scale — not part of the average above | ||
| AA Intelligence Index | 61.2 | 47.7 |
| AA Agentic Index | 51.5 | 23 |
| AA-Omniscience Index (−100–100) | 43.4 | 31.9 |
| GDPval-AA v2 | 1629.3 ELO | — |
| LMSYS Chatbot Arena | — | 1486.7 ELO |
| Providers | ||
| Available from |
OpenAI — $10.00/$50.00/Mtok
|
Google — $2.00/$12.00/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | GPT-6 Astra | Gemini 3.1 Pro | Savings |
|---|---|---|---|
| 1M tokens | $20 | $4.5 | $15.5 (77.5%) |
| 10M tokens | $200 | $45 | $155 (77.5%) |
| 100M tokens | $2000 | $450 | $1550 (77.5%) |
| 1000M tokens | $20000 | $4500 | $15500 (77.5%) |
When to pick which
distilled from the pricing and spec data above- raw capability matters more than price: 96 vs 74.8 average benchmark score
- cost dominates: $4.50/Mtok blended vs $20.00 — 77.5% less on the same 50/50 token mix
- you need the longer context: 2M tokens vs 1M (1.9×)
The cheaper option here — Gemini 3.1 Pro costs $4.50/Mtok blended on Google.
Summary
GPT-6 Astra by OpenAI costs $10.00/Mtok input and $50.00/Mtok output, with a 1M-token context window. It supports text, image input.
Gemini 3.1 Pro by Google costs $2.00/Mtok input and $12.00/Mtok output, with a 2M-token context window. It supports text, image, audio, video input.
On a blended cost basis, Gemini 3.1 Pro is 77.5% cheaper than GPT-6 Astra.It also has a larger context window.
On benchmarks, GPT-6 Astra scores higher (96 vs 74.8) on average. In terms of value, Gemini 3.1 Pro has better performance per dollar (16.6 vs 4.8).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.