GPT-4 Turbo vs GPT-6 Astra: price, context and capabilities

Choose GPT-4 Turbo for high-volume, cost-sensitive work and writing and code generation. Choose GPT-6 Astra for very long inputs, the latest release and the most recent knowledge.

In short

  • GPT-4 Turbo is 25% cheaper than GPT-6 Astra at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens).
  • GPT-6 Astra reads more per request: 1.05M tokens against 128k.
  • GPT-6 Astra is the newer model (Sep 3, 2026, against Apr 9, 2024).
  • Only GPT-6 Astra offers reasoning, prompt caching.

Open in the full comparison table

What a month costsAt 20 million input and 5 million output tokens a month.
  1. GPT-4 TurboOpenAI$350
  2. GPT-6 AstraOpenAI$450

Try your own volumes in the calculator

Which should you choose?

Each answer below comes straight from the published prices, specifications and independent benchmark results.

High-volume, cost-sensitive work

Choose GPT-4 Turbo

GPT-4 Turbo costs 25% less on a typical mix of three input tokens for every output token ($15.00 against $20.00 per million tokens).

Writing and code generation

Choose GPT-4 Turbo

GPT-4 Turbo charges $30.00 per million output tokens, against $50.00 for GPT-6 Astra. Output dominates the bill when answers are long.

Very long inputs

Choose GPT-6 Astra

GPT-6 Astra reads up to 1.05M tokens per request, against 128k for GPT-4 Turbo.

Latest release

Choose GPT-6 Astra

GPT-6 Astra is the newer release (Sep 3, 2026, against Apr 9, 2024 for GPT-4 Turbo).

Most recent knowledge

Choose GPT-6 Astra

GPT-6 Astra was trained on data up to April 2026, against December 2023 for GPT-4 Turbo.

Monthly cost at three volumes

VolumeGPT-4 TurboGPT-6 AstraDifference
Prototype: 1M input, 250K output tokens $17.50 $22.50 GPT-4 Turbo, $5.00 less
Production: 20M input, 5M output tokens $350.00 $450.00 GPT-4 Turbo, $100.00 less
Scale: 500M input, 100M output tokens $8,000 $10,000 GPT-4 Turbo, $2,000 less

Standard rates, without caching or batch discounts. Volumes are per month.

Specifications side by side

GPT-4 TurboGPT-6 Astra
ProviderOpenAIOpenAI
CategoryLanguage modelsLanguage models
StatusDeprecatedGenerally available
Headline price$15.00 / 1M tokens$20.00 / 1M tokens
Input$10.00 / 1M tokens$10.00 / 1M tokens
Output$30.00 / 1M tokens$50.00 / 1M tokens
Cached inputNo data$1.00 / 1M tokens
Context window128k1.05M
Max output4k128k
ReleasedApr 9, 2024Sep 3, 2026
Knowledge cutoffDecember 2023April 2026
LicenceProprietaryProprietary
CapabilitiesVision, Tool calling, Structured output, Batch APIVision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API
API model idgpt-4-turbogpt-6-astra

Benchmarks side by side

Leader in bold.

BenchmarkGPT-4 TurboGPT-6 Astra
Humanity's Last Exam 3.1% 54.7%
Intelligence Index No data 52.7
SciCode No data 56.5%
GPQA Diamond No data 96.1%
MMMU-Pro (visual reasoning) No data 86.9%
Long-context reasoning (AA-LCR) No data 80.7%

Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.

Frequently asked questions

Should I choose GPT-4 Turbo or GPT-6 Astra?

Choose GPT-4 Turbo for high-volume, cost-sensitive work and writing and code generation. Choose GPT-6 Astra for very long inputs, the latest release and the most recent knowledge.

Which is cheaper, GPT-4 Turbo or GPT-6 Astra?

GPT-4 Turbo is 25% cheaper than GPT-6 Astra at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens).

Which has the larger context window, GPT-4 Turbo or GPT-6 Astra?

GPT-6 Astra reads more per request: 1.05M tokens against 128k.

What is the difference between GPT-4 Turbo and GPT-6 Astra?

GPT-4 Turbo is made by OpenAI and GPT-6 Astra by OpenAI. GPT-4 Turbo is 25% cheaper than GPT-6 Astra at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens). GPT-6 Astra reads more per request: 1.05M tokens against 128k. GPT-6 Astra is the newer model (Sep 3, 2026, against Apr 9, 2024). Only GPT-6 Astra offers reasoning, prompt caching.

How much do GPT-4 Turbo and GPT-6 Astra cost per month?

At 20 million input and 5 million output tokens a month, GPT-4 Turbo costs $350.00 and GPT-6 Astra costs $450.00, at standard rates.

Which is newer, GPT-4 Turbo or GPT-6 Astra?

GPT-6 Astra was released on Sep 3, 2026 and GPT-4 Turbo on Apr 9, 2024.