OpenAI

GPT-5.6 Terra

Efficient variant for high-throughput workloads

Model Summary

Family

GPT-5.6

Version

5.6

Parameters

800B (est.)

Parameter counts for closed models are estimates; vendors rarely publish exact sizes.

VRAM Requirements by Quantization

Memory needed to serve GPT-5.6 Terra for inference, including a 20% overhead for activations and KV cache.

PrecisionVRAM neededSmallest single GPU that fits
INT4 (4-bit)447.03 GBMulti-GPU required
INT8 (8-bit)894.07 GBMulti-GPU required
FP16 (16-bit)1788.14 GBMulti-GPU required
FP32 (32-bit)3576.28 GBMulti-GPU required

Recommended GPU Configurations

Cheapest on-demand configurations to serve GPT-5.6 Terra at 8-bit (894 GB VRAM).

7x AMD Instinct MI250X

896 GB total VRAM · CDNA 2

~$17.50/h

56x NVIDIA T4

896 GB total VRAM · Turing · multi-node

~$28.00/h

5x AMD Instinct MI300X

960 GB total VRAM · CDNA 3

~$30.00/h

Quick GPU Planning

Use the calculator pre-filled with this exact version to estimate memory, speed, and compute requirements in a few clicks.

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Frequently Asked Questions

How much VRAM do you need to run GPT-5.6 Terra?

With an estimated 800B parameters, GPT-5.6 Terra needs roughly 894 GB of VRAM in 8-bit (INT8), 447 GB in 4-bit, and 1788 GB in FP16, including a 20% overhead for activations and KV cache.

Which GPUs can run GPT-5.6 Terra?

At 8-bit quantization, the most cost-effective option is 7x AMD Instinct MI250X (896 GB combined VRAM, around $17.50/hour on-demand). Higher-end cards like the NVIDIA B200 or AMD MI355X reduce the GPU count needed.

Can GPT-5.6 Terra run on a single GPU?

No. Even in 4-bit, GPT-5.6 Terra exceeds the memory of any single current GPU, so a multi-GPU cluster is required.

How much does it cost to serve GPT-5.6 Terra in the cloud?

Renting 7x Instinct MI250X costs on the order of $17.50/hour, i.e. about $12,775/month running 24/7. Actual prices vary by provider and commitment; spot and reserved capacity can be significantly cheaper.

Other GPT-5.6 Versions