Best LLMs for Structured Output Extraction
Extracts structured data from text into a specified JSON schema. Pure shape-conformance — no enrichment, no rephrasing, no summarisation. Used when a downstream consumer needs schema-clean data from prose.
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Models
Frontier on this task: Claude Opus 5.5 at 9.93 / 10. Score needed at the Balanced step: 8.94.
point-estimate floor (CI low) · upper CI (less certain) · Bars sorted by blended cost; best-value model first. Greyed rows are MEDIUM+ models whose point estimate does not clear the bar.
| Model | Quality score | CI low | Cost / 1k runs | vs best value |
|---|---|---|---|---|
| Xiaomi MiMo V2.6 Flash | 9.76 / 10 | 9.54 | $0.74 | best value |
| GPT-6 Luna | 9.11 / 10 | 8.84 | $1.91 | 2.6x more expensive |
| Xiaomi MiMo V2.6 Pro | 9.64 / 10 | 9.38 | $2.20 | 3x more expensive |
| DeepSeek V4.1 Flash | 9.25 / 10 | 8.92 | $3.03 | 4.1x more expensive |
| MiniMax M3 | 9.12 / 10 | 8.97 | $4.52 | 6.1x more expensive |
| GPT-6 Sol | 9.20 / 10 | 8.88 | $23.42 | 32x more expensive |
| Qwen 3.7 Plus | 9.56 / 10 | 9.40 | $26.93 | 36x more expensive |
| Claude Sonnet 5.5 | 9.88 / 10 | 9.71 | $33.92 | 46x more expensive |
| Claude Opus 5.5 | 9.93 / 10 | 9.77 | $68.07 | 92x more expensive |
| Moonshot Kimi K3 | 9.59 / 10 | 9.29 | $82.63 | 112x more expensive |
| Qwen 3.8 Max | 9.32 / 10 | 8.93 | $139.28 | 188x more expensive |
| Grok 4.7 | 8.26 / 10 | 7.93 | $32.33 | 44x more expensive |
| Gemini 3.5 Flash Lite | 8.23 / 10 | 7.77 | $5.60 | 7.6x more expensive |
| Gemini 3.8 Flash | 8.14 / 10 | 7.81 | $9.96 | 13x more expensive |
| Thinking Machines Inkling Small | 8.40 / 10 | 7.91 | $7.20 | 9.7x more expensive |
| Claude Haiku 5.5 | 8.52 / 10 | 8.11 | $1.72 | 2.3x more expensive |
Cost breakdown
| Model | Quality | Confidence | Cost / 1k runs | Overpay | Mode |
|---|---|---|---|---|---|
| Xiaomi MiMo V2.6 Flash ★ Xiaomi MiMo | 9.76 / 10 CI [9.54, 9.98] | HIGH | $0.74 | best value | batch |
| GPT-6 Luna OpenAI | 9.11 / 10 CI [8.84, 9.38] | HIGH | $1.91 | 2.6x | batch |
| Xiaomi MiMo V2.6 Pro Xiaomi MiMo | 9.64 / 10 CI [9.38, 9.89] | HIGH | $2.20 | 3x | batch |
| DeepSeek V4.1 Flash DeepSeek | 9.25 / 10 CI [8.92, 9.58] | MEDIUM | $3.03 | 4.1x | batch |
| MiniMax M3 OpenRouter | 9.12 / 10 CI [8.97, 9.28] | RANKED | $4.52 | 6.1x | batch |
| GPT-6 Sol OpenAI | 9.20 / 10 CI [8.88, 9.53] | MEDIUM | $23.42 | 32x | batch |
| Qwen 3.7 Plus Alibaba Cloud (DashScope) | 9.56 / 10 CI [9.40, 9.72] | RANKED | $26.93 | 36x | batch |
| Claude Sonnet 5.5 Anthropic | 9.88 / 10 CI [9.71, 10.00] | RANKED | $33.92 | 46x | batch |
| Claude Opus 5.5 best Anthropic | 9.93 / 10 CI [9.77, 10.00] | RANKED | $68.07 | 92x | batch |
| Moonshot Kimi K3 Moonshot AI | 9.59 / 10 CI [9.29, 9.89] | HIGH | $82.63 | 112x | batch |
| Qwen 3.8 Max Alibaba Cloud (DashScope) | 9.32 / 10 CI [8.93, 9.71] | MEDIUM | $139.28 | 188x | batch |
Overpay shows how much more you pay than the best-value model that meets the quality step (marked ★) — the best-value good-enough option. "16x" means you overpay 16× — 16× that reference for no quality benefit the step asks for. Typical call shape for this task: 3211 input tokens → 12079 output tokens, EMA-tracked from production traffic. Cost is the observed, all-in $ per 1,000 task runs: each model's own measured usage on this task — output verbosity, thinking/reasoning tokens, cache reads and writes, and the spend on its billed failures — priced at current list rates and adjusted by the billing overhead we actually reconcile against provider invoices. Models that answer tersely cost what they actually cost; models that think at length pay for it. Not comparable to providers' advertised $/1M list rates — this is what running the task costs, not a per-token price.
Evaluation rubric
Judge field-level source support, completeness for present values, correct missing-value handling, semantic and quantitative fidelity, resistance to embedded instructions, and absence of enrichment. JSON/schema validity is deterministic.
Output schema
Every answer on this task is checked against this JSON Schema, whichever model wrote it. An answer that doesn't fit counts as a model failure, and the call is retried on another model.
{
"properties": {
"report_markdown": {
"description": "The full synthesized report formatted in Markdown.",
"title": "Report Markdown",
"type": "string"
}
},
"required": [
"report_markdown"
],
"title": "SynthesizedOutputMarkdownOnly",
"type": "object"
}Prompt templates
The published template for this task.
default ·
STRUCTURED_OUTPUT_EXTRACTION_SYSTEM_PROMPT +
STRUCTURED_OUTPUT_EXTRACTION_USER_PROMPT
(2695 calls in window)
System prompt
You are a JSON extraction assistant. Extract structured data from the provided text that matches the given JSON schema. Output ONLY the structured data matching the schema.
User prompt
Extract the structured data from the following text that matches this JSON schema:
## JSON Schema:
```json
{schema_json}
```
## Text to extract from:
{raw_text}