Model comparison

Gemini 3.1 Pro vs GPT-6 Astra

Compare published specifications, vendor API list prices and measured Borg performance. Both models are included in Borg.

Gemini 3.1 Pro

1,048,576 tokensContext window
—Median time to first token (gateway proxy)
—Output tokens per second (whole turn)
—Request success
$2 / $12Vendor API price in / out · per 1M

GPT-6 Astra

1,050,000 tokensContext window
4780 msMedian time to first token (gateway proxy)
16Output tokens per second (whole turn)
99.6%Request success
$10 / $50Vendor API price in / out · per 1M

Included in Borg

At a glance

SpecificationGemini 3.1 ProGPT-6 Astra
ProviderGoogleOpenAI
Release2026-02-19 Vendor source2026-09-03 Vendor source
Context1,048,576 tokens Vendor source1,050,000 tokens Vendor source
ModalitiesInput: text, image, video, audio, pdf; output: textInput: text, image; output: text
Reasoning / thinking modesYes / Not publishedYes / Not published
Open weightsNoNo
Vendor API list price / 1M tokens$2 input / $12 output Rates for prompts of at most 200,000 tokens; longer prompts cost more.$10 input / $50 output Standard global rates for prompts up to 272,000 input tokens. Above 272,000 input tokens, input and cached-input rates are 2× and output rates are 1.5× for the full request.
BorgIncluded in Borg subscriptionIncluded in Borg subscription

Measured on Borg

Metrics are not directly comparable to vendor benchmark claims. Models served different requests; this is observed gateway traffic, not a controlled head-to-head test.

Time to first token (gateway proxy)

Output tokens per second (whole turn)

MetricGemini 3.1 ProGPT-6 Astra
Time to first token (gateway proxy) p50Not published4780 ms (1335 samples)
Tokens per second (end to end) p50Not published16 output tokens per second (18243 samples)
Request success rateNot published99.6% (2222 samples)
Coding bench pass rateNot published67% (15 samples)
Measurement window, samples and methodology

The fleet reference is the median of published model medians, not a request-weighted result. Prompt lengths, reasoning settings and traffic differ between models.

Gemini 3.1 Pro: Measured on Borg: SearchAtlas AI Gateway production request logs. 30-day window ending 2026-10-08; 278 requests. Minimum 100 samples per published request metric.

GPT-6 Astra: Measured on Borg: SearchAtlas AI Gateway production request logs. 30-day window ending 2026-10-08; 20969 requests. Minimum 100 samples per published request metric.

Completion speed covers the whole turn including queueing and reasoning time; it is not a streaming tokens-per-second figure.

  • Time to first token (gateway proxy): time until the first streamed response event reaches the gateway; our closest available measure of time to first token
  • Tokens per second (end to end): tokens per second, end to end: provider-reported output tokens divided by the whole turn's elapsed time, including queueing and reasoning; not a streaming per-token rate

How to choose

Gemini 3.1 Pro is listed for complex software engineering, whereas GPT-6 Astra is listed for hard coding assignments. Choosing between Gemini 3.1 Pro and GPT-6 Astra requires checking published specifications against observed Borg traffic for your workflow.

Key differences

SpecGemini 3.1 ProGPT-6 Astra
Context window1,048,576 tokens Vendor source1,050,000 tokens Vendor source Larger context
Reasoning modesYes / Not publishedYes / Not published
Release date2026-02-19 Vendor source2026-09-03 Vendor source
API price input / 1M2 Rates for prompts of at most 200,000 tokens; longer prompts cost more. Lower listed rate10 Standard global rates for prompts up to 272,000 input tokens. Above 272,000 input tokens, input and cached-input rates are 2× and output rates are 1.5× for the full request.
API price output / 1M12 Rates for prompts of at most 200,000 tokens; longer prompts cost more. Lower listed rate50 Standard global rates for prompts up to 272,000 input tokens. Above 272,000 input tokens, input and cached-input rates are 2× and output rates are 1.5× for the full request.
Time to first token (gateway proxy)Not published4780 ms (1335 samples)
Output tokens per second (whole turn)Not published16 output tokens/s (whole turn) (18243 samples)
Request successNot published99.6% (2222 samples)
Coding benchNot published67% (15 samples)

FAQ

How do Gemini 3.1 Pro and GPT-6 Astra compare for coding?

Gemini 3.1 Pro has a Borg coding benchmark of not published; GPT-6 Astra has 66.67% pass rate across 15 samples and 3 tasks. The Gemini 3.1 Pro–GPT-6 Astra coding comparison cannot establish an overall winner from this small test alone.

How quickly do Gemini 3.1 Pro and GPT-6 Astra start responding on Borg?

Borg median first response for Gemini 3.1 Pro is not published; for GPT-6 Astra it is 4,780 ms. The Gemini 3.1 Pro–GPT-6 Astra gateway medians are observations, not guaranteed latency for individual requests.

What are the API prices for Gemini 3.1 Pro and GPT-6 Astra?

The listed API rate for Gemini 3.1 Pro is $2 input / $12 output per 1M tokens; for GPT-6 Astra it is $10 input / $50 output per 1M tokens. Neither Gemini 3.1 Pro nor GPT-6 Astra has its Borg subscription charge represented by those provider API rates. Gemini 3.1 Pro vendor source · GPT-6 Astra vendor source

Explore both models

Gemini 3.1 Pro · GPT-6 Astra · Borg pricing

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