Gemini 4 Carbon vs GPT-6 Astra

Pick a route and service tier under each model. Prices, the calculator and the verdicts follow your choice.

Try Gemini 4 Carbon in Chat

At a glance

Generated from the rows below

Choose Gemini 4 Carbon for

The lowest cost per typical request ($0.009)
The only one that takes audio, video
Included in 25 subscription plans

Choose GPT-6 Astra for

The largest context window: 1,050,000 tokens
The longest output: 128,000 tokens

The models are statistically tied on the Epoch Capabilities Index: their 95% confidence intervals overlap.

Overview

Lab

Google

OpenAI

Context window

1.049Mtokensfrom provider listings

1.05Mtokens

Max output

65.5Ktokensfrom provider listings

128Ktokens

Takes

Returns

Routes on Phaseo

2 providers

Released

10 Nov 2026

3 Sept 2026

Pricing

Prices on the route and tier chosen under each model

Priced onGoogle AI Studio · StandardOpenAI · Standard

Input

$2.00/ 1M tokens

from $10.00/ 1M tokensInput ≤ 272K$10.00Input > 272K$20.00

Output

$10.00/ 1M tokens

from $50.00/ 1M tokensInput ≤ 272K$50.00Input > 272K$75.00

Cache read

$0.10/ 1M tokens

from $1.00/ 1M tokensInput ≤ 272K$1.00Input > 272K$2.00

Cache write

No write fee listed

from $12.50/ 1M tokensInput ≤ 272K$12.50Input > 272K$25.00

Typical request2K tokens in, 500 out

$0.009

$0.045

What will it cost?

Estimate a month of requests on the route and tier chosen for each model

Input tokens per request

Output tokens per request

Cached share of input (%)

Requests per day

ModelMonthly costPer requestPer month

Gemini 4 CarbonGoogle AI Studio · Standard$0.009$270.00

GPT-6 AstraOpenAI · Standard$0.045$1,350

Uses the route and tier chosen under each model, over 30 days. Cached input is billed at the cache-read rate.

Performance

Live gateway traffic

Latency p50last 5 days

17.5 s

No traffic in the last 5 days

Throughput p50last 5 days

15.3 tps

No traffic in the last 5 days

Requests, last 24 hours

None in the last 24 hours

Activity

Tokens sent through Phaseo each day over the last 30 days

Tokens, last 30 days

24.7K

406

Per day

24.7K

16 Oct14 Nov

406

16 Oct14 Nov

Input

21.8K

216

Output

1.66K

190

Reasoning

1.2K

Requests

Features

Features from the parameters Phaseo routes support

Tool calling

Yes

Structured outputs

Yes

Reasoning effort

Yes

Web search

Not listed

Yes

Prompt cachingon the chosen route

Yes

Quantisationon the chosen route

Not stated

Benchmarks

Only results that two or more of the selected models report get a row

Compare at effort

Epoch Capabilities Index Independent

Higher is better · dot is the estimate, band is the 95% confidence interval · Epoch AI, CC BY 4.0

Gemini 4 Carbon169.8

GPT-6 Astra169.0

Every interval overlaps, so these models are statistically tied on this index.

Artificial Analysis Intelligence Index Independent

Higher is better · at High effort · 2 of 2 models tested

Gemini 4 Carbon60

GPT-6 Astra54.8

Where they rank

The five leaders on each capability index, then the compared models. Each model at its best-scoring setting.

Artificial Analysis Intelligence Index62 models ranked

Artificial Analysis Coding Index168 models ranked

Artificial Analysis Agentic Index110 models ranked

Epoch Capabilities Index165 models ranked

Cost

Artificial Analysis Evaluation Cost (USD)matched by effort level · lower is better

$5,333

$3,204

General

Artificial Analysis Progress Index v1matched by effort level

350.8

347.4

Agents

Agents' Last Examreported by the lab

77.4%

59.3%

OSWorld 2.1reported by the lab

81.5%

80.9%OSWorld 2.1, offline set

Code

Terminal Bench 4.0reported by the lab

65.2%

58.2%Terminal-Bench 4.0

Science

Terminal-Bench Science 0.1reported by the lab

64.8%

68.1%Terminal-Bench-Science 0.1

Lab-reported results come from each lab’s own launch materials and may use different settings, so none is marked best. Independent results come from third-party evaluators.

Providers

Where each model runs on Phaseo, with standard-tier prices per 1M tokens. Providers that serve more of these models come first.

Google AI Studio

$2.00 in · $10.00 out1.05M context · Standard, Batch, Flex, Priority

—

OpenAI

—

$10.00 in · $50.00 out$10.00 per 1K requests Native web search requests1.05M context · Standard, Batch, Flex, Priority, Ultrafast

Google Vertex

$2.00 in · $10.00 out1.05M context · Standard, Batch, Flex, Priority

—

Inference.net

—

$10.00 in · $50.00 out922K context

Also listed, not routed

—

4 providers

To price the whole page on one of these providers, pick it under the model’s name at the top.

Details

Knowledge cutoff

Not published

Apr 2026

Status

Available

Licence

Proprietary

Subscription plans

25 plansCursor Enterprise, Cursor Pro, Cursor Pro+…

23 plansChatGPT Business, ChatGPT Business Codex, ChatGPT Business Premium…

API docs

Not published

Open docs

Gemini 4 Carbon vs GPT-6 Astra: side-by-side summary

Gemini 4 Carbon and GPT-6 Astra are both available through the Phaseo API, so switching between them is a change of model id rather than a new integration.

Gemini 4 Carbon is from Google. It has a 1,048,576-token context window. On its cheapest route it costs $2.00 per 1M input tokens and $10.00 per 1M output tokens.

GPT-6 Astra is from OpenAI. It has a 1,050,000-token context window. On its cheapest route it costs $10.00 per 1M input tokens and $50.00 per 1M output tokens.

Gemini 4 Carbon model details, providers and pricing GPT-6 Astra model details, providers and pricing

Gemini 4 Carbon vs GPT-6 Astra at a glance

Gemini 4 Carbon and GPT-6 Astra compared on price, context window and benchmark score
Attribute	Gemini 4 Carbon	GPT-6 Astra
Lab	Google	OpenAI
Input price per 1M tokens	$2.00	$10.00
Output price per 1M tokens	$10.00	$50.00
Context window	1,048,576 tokens	1,050,000 tokens
Max output	65,536 tokens	128,000 tokens
Artificial Analysis Intelligence Index	60.0 (#2)	56.9 (#4)

Prices are each model's cheapest standard route on Phaseo. Benchmark ranks use each model's best-scoring evaluated setting.

Frequently asked questions

Which is cheaper, Gemini 4 Carbon or GPT-6 Astra?

Gemini 4 Carbon is cheaper for both input and output tokens. Gemini 4 Carbon costs $2.00 per 1M input tokens and $10.00 per 1M output tokens; GPT-6 Astra costs $10.00 and $50.00, each on its cheapest standard route on Phaseo.

Which has the longer context window, Gemini 4 Carbon or GPT-6 Astra?

GPT-6 Astra has the longer context window at 1,050,000 tokens, compared with 1,048,576 tokens for Gemini 4 Carbon.

Which scores higher on the Artificial Analysis Intelligence Index, Gemini 4 Carbon or GPT-6 Astra?

Gemini 4 Carbon scores higher on the Artificial Analysis Intelligence Index. Gemini 4 Carbon scores 60.0, ranked #2 of 62. GPT-6 Astra scores 56.9, ranked #4 of 62.

Can I use Gemini 4 Carbon and GPT-6 Astra through one API?

Yes. Both are served through the Phaseo API, so you can switch between them by changing the model id.