AI model comparison

GPT-5.6 Terra vs GPT-5.4

Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.

GPT-5.6 Terra is a balanced model in OpenAI's GPT-5.6 series, positioned between the flagship Sol tier and the cost-efficient Luna tier.

Input / 1M
$2
Output / 1M
$12
Context
1.05M
openai logo

OpenAI

GPT-5.4

GPT-5.4 is OpenAI’s latest frontier model, unifying the Codex and GPT lines into a single system.

Input / 1M
$2.50
Output / 1M
$15
Context
1.05M

At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

openai logo

GPT-5.6 Terra

1.3x cheaper for a typical chat

Higher intelligence score

openai logo

GPT-5.6 Terra

42.1 vs 39 on Artificial Analysis

Larger context window

Tie

1.05M vs 1.05M tokens

Newer release

openai logo

GPT-5.6 Terra

Released July 9, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

openai logoGPT-5.6 Terra42.1
openai logoGPT-5.439

Coding index

openai logoGPT-5.6 Terra76.7
openai logoGPT-5.471.1

Agentic index

openai logoGPT-5.6 Terra43.2
openai logoGPT-5.4Not available

Pricing

GPT-5.6 Terra vs GPT-5.4 API pricing

Per-token API rates. Cheaper option highlighted.

Metricopenai logoGPT-5.6 Terraopenai logoGPT-5.4
Input tokensPer 1M tokens$2$2.50
Output tokensPer 1M tokens$12$15
Cached input (read)Per 1M tokens$0.20$0.25
Cache writePer 1M tokens$2.50Not available
Long-context pricingPer 1M tokens, for very long prompts$4 in / $18 out above 272K$5 in / $22.50 out above 272K
Web searchPer request$0.01$0.01

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

openai logoGPT-5.6 Terra$10
openai logoGPT-5.4$12.50

Coding task

30K in, 4K out

openai logoGPT-5.6 Terra$108$54 cached
openai logoGPT-5.4$135$67.50 cached

Long document summary

150K in, 2K out

openai logoGPT-5.6 Terra$324$54 cached
openai logoGPT-5.4$405$67.50 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metricopenai logoGPT-5.6 Terraopenai logoGPT-5.4
Context window1.05M tokens1.05M tokens
Max output128K tokens128K tokens
Input typesFile, Image, TextFile, Image, Text
Output typesTextText
Reasoning effort levelsMax, Extra high, High, Medium, Low, NoneExtra high, High, Medium, Low, None
Default reasoning effortMediumMedium
Release dateJuly 9, 2026March 5, 2026

Features

Supported features

API features available for each model.

Metricopenai logoGPT-5.6 Terraopenai logoGPT-5.4
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureNot supportedNot supported
Stop sequencesNot supportedNot supported
Deterministic seedSupportedSupported
Verbosity controlSupportedSupported

Our take

GPT-5.6 Terra is 1.3x cheaper for a typical chat. GPT-5.6 Terra scores higher on the Artificial Analysis Intelligence Index (42.1 vs 39). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is GPT-5.6 Terra or GPT-5.4 cheaper?

GPT-5.6 Terra is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-5.6 Terra costs $2 per 1M input tokens and $12 per 1M output tokens, while GPT-5.4 costs $2.50 per 1M input tokens and $15 per 1M output tokens.

Which has a bigger context window, GPT-5.6 Terra or GPT-5.4?

GPT-5.6 Terra supports up to 1.05M tokens of context, compared with 1.05M for GPT-5.4.

Is GPT-5.6 Terra smarter than GPT-5.4?

On the Artificial Analysis Intelligence Index, GPT-5.6 Terra scores 42.1 and GPT-5.4 scores 39, putting GPT-5.6 Terra ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.

Can I use GPT-5.6 Terra and GPT-5.4 at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-5.6 Terra and GPT-5.4 answer side by side and keep the better response.

openai logoopenai logo

Why choose? Ask both.

Send one prompt to GPT-5.6 Terra and GPT-5.4 at the same time. Compare the answers side by side and keep the best one.