GPT-5.6 Terra vs DeepSeek V4 Flash 0420: Release Comparison

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

Comparison of the GPT-5.6 Terra and DeepSeek V4 Flash 0420 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 DeepSeek V4 Flash (Reasoning, High Effort) at 25 for DeepSeek V4 Flash 0420.
For cost per task, DeepSeek V4 Flash 0420 is cheapest: DeepSeek V4 Flash (Reasoning, Max Effort) at $0.12, against GPT-5.6 Terra (Non-reasoning) at $0.14 for GPT-5.6 Terra.

Releases compared

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index v4.3 incorporates 10 evaluations: AA-Briefcase, GDPval-AA v2, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1

Estimate (independent evaluation forthcoming)

Artificial Analysis Intelligence Index v4.3 includes: AA-Briefcase, GDPval-AA v2, 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

DeepSeek V4 Flash 0420

Pareto line

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

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 (e.g. OpenAI for o1) or the median across providers where a first-party API is not available (e.g. Meta's Llama models).

Capability Scores

Capability Indices

Measures the performance of models on specific capabilities and industries

Finance & Accounting Index

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

Strategy & Ops Index

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

Legal Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2, AA-Briefcase, 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, AA-Briefcase, 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, AA-Briefcase, Terminal-Bench 4.0 · Higher is better

Economics Index

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

Further details


																												Input modality	Output modality	Weights			Provider Benchmarks
GPT-5.6 Terra (max)	OpenAI	42	42	48	42	41	43	45	$1.40	$1.7	$2.00	$12.00	$0.20	$2,501	39k	26k	122M	99	139.76s	139.76s	144.82s	393.54s	-	1M	Jul 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
GPT-5.6 Terra (xhigh)	OpenAI	38	40	44	40	38	38	44	$0.63	$1.7	$2.00	$12.00	$0.20	$1,187	20k	12k	52M	92	14.46s	14.46s	19.92s	230.84s	-	1M	Jul 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
GPT-5.6 Terra (high)	OpenAI	34	38	40	37	34	35	42	$0.34	$1.7	$2.00	$12.00	$0.20	$768	11k	5k	33M	91	2.80s	2.80s	8.29s	123.23s	-	1M	Jul 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
GPT-5.6 Terra (medium)	OpenAI	30	32	35	34	31	31	37	$0.18	$1.7	$2.00	$12.00	$0.20	$447	5k	2k	17M	89	1.72s	1.72s	7.33s	61.43s	-	1M	Jul 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
GPT-5.6 Terra (low)	OpenAI	28	30	32	31	28	28	35	$0.14	$1.7	$2.00	$12.00	$0.20	$350	4k	1k	11M	90	1.58s	1.58s	7.13s	43.37s	-	1M	Jul 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
DeepSeek V4 Flash (Reasoning, High Effort)	DeepSeek	25	29	29	29	26	26	34	$0.19	$0.1	$0.13	$0.28	$0.028	$210	42k	26k	128M	-	-	-	-	-	284B 13B active at inference time	1M	Apr 2026	-	Yes	Supports: text	Supports: text	🤗	MIT	+4	View
DeepSeek V4 Flash (Reasoning, Max Effort)	DeepSeek	25	28	28	28	27	27	33	$0.12	$0.1	$0.13	$0.28	$0.028	$191	55k	41k	250M	-	-	-	-	-	284B 13B active at inference time	1M	Apr 2026	-	Yes	Supports: text	Supports: text	🤗	MIT	+2	View
GPT-5.6 Terra (Non-reasoning)	OpenAI	21	22	24	23	-	21	24	$0.14	$1.7	$2.00	$12.00	$0.20	$256	3k	0	6M	93	0.88s	0.88s	6.28s	33.72s	-	1M	Jul 2026	-	No	Supports: text and image	Supports: text	Not available	-		View
DeepSeek V4 Flash (Non-reasoning)	DeepSeek	19	-	-	-	-	-	-	-	$0.1	$0.0938	$0.195	$0.07	-	-	-	-	-	-	-	-	-	284B 13B active at inference time	1M	Apr 2026	-	No	Supports: text	Supports: text	🤗	Mit		View

GPT-5.6 Terra vs DeepSeek V4 Flash 0420: Release Comparison

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 Indices

Further details