GPT-5.6 Terra vs K2-V2: Release Comparison

Name: Intelligence
Creator: Artificial Analysis
License: https://artificialanalysis.ai/docs/legal/Terms-of-Use.pdf

Comparison of the GPT-5.6 Terra and K2-V2 releases: 6 and 3 models respectively, each with different intelligence, performance, and pricing characteristics. Below is a comparison of the key metrics across all 9 models.

For intelligence, GPT-5.6 Terra scores highest: GPT-5.6 Terra (Max) at 42, against K2-V2 (High) at 10 for K2-V2.

Model Playground

Releases compared


	GPT-5.6 Terra (max)	GPT-5.6 Terra (xhigh)	GPT-5.6 Terra (high)	GPT-5.6 Terra (medium)	GPT-5.6 Terra (low)	GPT-5.6 Terra (non-reasoning)	K2-V2 (high)	K2-V2 (medium)	K2-V2 (low)
Intelligence Index	42	38	34	30	27	21	10*	9*	7*
Finance & Accounting	41	40	37	32	30	21	--	--	--
Strategy & Ops	47	44	40	34	31	23	--	--	--
Legal	41	40	37	34	31	22	--	--	--
Healthcare & Medical	40	38	34	31	27	--	--	--	--
Engineering	43	38	34	31	28	21	--	--	--
Economics	45	44	42	37	34	24	--	--	--
AA-Briefcase v1.1	1334	1333	1202	1039	1014	947	--	--	--
GDPval-AA v2.1	1451	1447	1376	1264	1108	1097	--	--	--
AutomationBench-AA	59.6%	47.1%	42.0%	33.5%	29.1%	12.5%	--	--	--
Terminal-Bench 4.0	35.4%	10.1%	1.5%	1.0%	1.5%	0.5%	--	--	--
SciCode	55.0%	52.3%	52.4%	50.5%	49.9%	45.1%	--	--	--
Humanity's Last Exam	42.9%	41.9%	38.5%	33.3%	29.2%	11.4%	10.5%	4.4%	3.6%
GDP.pdf	24.0%	24.6%	20.8%	17.0%	17.6%	11.2%	--	--	--
CritPt	30.0%	27.1%	22.9%	17.4%	9.4%	2.0%	0.0%	0.0%	0.0%
AA-Omniscience	0	−3	−3	−5	−7	−23	−56	−49	−47
AA-LCR v1.1	83.0%	79.0%	77.7%	74.0%	71.3%	58.7%	35.0%	28.0%	20.3%

Cost per TaskUSD	$1.40	$0.63	$0.34	$0.18	$0.14	$0.14	--	--	--
Input PriceUSD/1M Tokens	$2.00	$2.00	$2.00	$2.00	$2.00	$2.00	--	--	--
Output PriceUSD/1M Tokens	$12.00	$12.00	$12.00	$12.00	$12.00	$12.00	--	--	--
Cache Hit PriceUSD/1M Tokens	$0.20	$0.20	$0.20	$0.20	$0.20	$0.20	--	--	--
Cache Write PriceUSD/1M Tokens	$2.50	$2.50	$2.50	$2.50	$2.50	$2.50	--	--	--

Output SpeedTokens/s	123	110	102	103	100	100	--	--	--
Time to First Tokens	149.29	37.76	7.05	1.65	1.45	0.69	--	--	--
Time to First Answer Tokens	149.29	37.76	7.05	1.65	1.45	0.69	--	--	--
End-to-End Response Times	153.35	42.29	11.95	6.53	6.45	5.67	--	--	--
Time per Tasks	307.79	179.96	109.99	54.09	37.94	31.13	--	--	--

Context Window	1M	1M	1M	1M	1M	1M	512k	512k	512k
Creator	OpenAI	OpenAI	OpenAI	OpenAI	OpenAI	OpenAI	Institute of Foundation Models	Institute of Foundation Models	Institute of Foundation Models
License	Proprietary	Proprietary	Proprietary	Proprietary	Proprietary	Proprietary	Open	Open	Open
Input Modality	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text	Supports: text	Supports: text
Output Modality	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text
Providers							--	--	--

* Estimated

Intelligence

Artificial Analysis Intelligence Index · Higher is better

Speed

Output tokens per second · Higher is better

Cost per Task

Weighted average cost (USD) per Intelligence Index task · Lower is better

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index v4.3.2 incorporates 10 evaluations: AA-Briefcase v1.1, GDPval-AA v2.1, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1

No publicly available API

Estimate (independent evaluation forthcoming)

Artificial Analysis Intelligence Index v4.3.2 includes: AA-Briefcase v1.1, GDPval-AA v2.1, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1. See Intelligence Index methodology for further details, including a breakdown of each evaluation and how we run them.

Intelligence Index vs. Cost per Intelligence Index Task

Artificial Analysis Intelligence Index · Weighted average cost (USD) per Artificial Analysis Intelligence Index task

Most attractive quadrant

GPT-5.6 Terra

Pareto line

AA-Briefcase v1.1

GDPval-AA v2.1

Cost per Task (USD, Log Scale)

Weighted average cost per Intelligence Index task. Each evaluation’s cost is calculated from input, cache hit, cache write, reasoning, and answer token prices, divided by task count, and weighted by its Intelligence Index weight.

Cost

Cost per Intelligence Index Task

Weighted average cost (USD) per Artificial Analysis Intelligence Index task, segmented by token type. Lower is better

No publicly available API

Speed & Latency

Output Speed

Output tokens per second · Higher is better

Tokens per second received while the model is generating tokens (ie. after first chunk has been received from the API for models which support streaming).

Figures represent performance of the model's first-party API or the median across providers where a first-party API is not available.

Capability Scores

Capability Indexes

Measures the performance of models on specific capabilities and industries

Finance & Accounting Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, Humanity's Last Exam, AutomationBench-AA, AA-LCR v1.1, GDP.pdf · Higher is better

Strategy & Ops Index

Incorporates 6 evaluations: GDPval-AA v2.1, AA-Briefcase v1.1, AA-Omniscience, AutomationBench-AA, AA-LCR v1.1, GDP.pdf · Higher is better

Legal Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, Humanity's Last Exam, AA-LCR v1.1, GDP.pdf, AutomationBench-AA · Higher is better

Healthcare & Medical Index

Incorporates 6 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, MLCR-AA, Humanity's Last Exam, AutomationBench-AA · Higher is better

Engineering Index

Incorporates 6 evaluations: AA-Omniscience, Humanity's Last Exam, CritPt, GDPval-AA v2.1, AA-Briefcase v1.1, Terminal-Bench 4.0 · Higher is better

Economics Index

Incorporates 5 evaluations: AA-Omniscience, Humanity's Last Exam, GDPval-AA v2.1, AA-Briefcase v1.1, AA-LCR v1.1 · Higher is better

GPT-5.6 Terra vs K2-V2: Release Comparison

Intelligence

Speed

Cost per Task

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index

Intelligence Index vs. Cost per Intelligence Index Task

Cost per Intelligence Index Task

Artificial Analysis Intelligence Index

Cost

Cost per Intelligence Index Task

Cost per Intelligence Index Task

Speed & Latency

Output Speed

Output Speed

Model Performance Representation

Capability Scores

Capability Indexes