{ } Curated ranking

Cheapest AI models with structured JSON output

Models that honor a strict JSON schema (not just "return JSON"). Critical for data pipelines where downstream code expects guaranteed shape. Ranked by input price ascending — cheapest schema-mode model first.

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#	Model	Provider	Input price	Lifecycle	Verified
1	gpt-oss-20b OpenAI · Active	OP OpenAI	$0.03/M input	Active	· 10h ago
2	gpt-oss-120b OpenAI · Active	OP OpenAI	$0.04/M input	Active	· 10h ago
3	GPT-5 Nano OpenAI · Active	OP OpenAI	$0.05/M input	Active	· 10h ago
4	GPT-4.1 Nano OpenAI · Active	OP OpenAI	$0.1/M input	Active	· 10h ago
5	Gemini 2.0 Flash Google Gemini · Active	GG Google Gemini	$0.1/M input	Active	· 10h ago
6	Gemini 2.5 Flash-Lite Google Gemini · Active	GG Google Gemini	$0.1/M input	Active	· 10h ago
7	GPT-4o Mini OpenAI · Active	OP OpenAI	$0.15/M input	Active	· 10h ago
8	GPT-5.4 Nano OpenAI · Active	OP OpenAI	$0.2/M input	Active	· 10h ago
9	GPT-5 Mini OpenAI · Active	OP OpenAI	$0.25/M input	Active	· 10h ago
10	Gemini 2.5 Flash Google Gemini · Active	GG Google Gemini	$0.3/M input	Active	· 10h ago
11	GPT-4.1 Mini OpenAI · Active	OP OpenAI	$0.4/M input	Active	· 10h ago
12	Gemini 3.1 Flash-Lite Google Gemini · Active	GG Google Gemini	$0.5/M input	Active	· 10h ago
13	GPT-5.4 Mini OpenAI · Active	OP OpenAI	$0.75/M input	Active	· 10h ago
14	Grok Build 0.1 xAI · Active	XA xAI	$1/M input	Active	· 10h ago
15	o4-mini OpenAI · Active	OP OpenAI	$1.1/M input	Active	· 10h ago
16	GPT-5 OpenAI · Active	OP OpenAI	$1.25/M input	Active	· 10h ago
17	GPT-5.1 OpenAI · Active	OP OpenAI	$1.25/M input	Active	· 10h ago
18	Gemini 2.5 Pro Google Gemini · Active	GG Google Gemini	$1.25/M input	Active	· 10h ago
19	Grok 4.20 xAI · Active	XA xAI	$1.25/M input	Active	· 10h ago
20	Grok 4.3 xAI · Active	XA xAI	$1.25/M input	Active	· 10h ago
21	Gemini 3.5 Flash Google Gemini · Active	GG Google Gemini	$1.5/M input	Active	· 10h ago
22	GPT-5.2 OpenAI · Active	OP OpenAI	$1.75/M input	Active	· 10h ago
23	GPT-4.1 OpenAI · Active	OP OpenAI	$2/M input	Active	· 10h ago
24	o3 OpenAI · Active	OP OpenAI	$2/M input	Active	· 10h ago
25	Gemini 3.1 Pro Preview Google Gemini · Active	GG Google Gemini	$2/M input	Active	· 10h ago

Showing top 25 of 31 matches.

Methodology

How this ranking is built

Active models that honor a strict JSON schema (not just "return JSON-ish text") and have a published input price. Ranked from cheapest input cost upward.

Refreshed as we re-verify each model against its provider's official docs. Every value links to the page it came from. Last updated Jun 8, 2026 06:01 UTC.