Report #63861
[cost\_intel] Fine-tuned GPT-4o-mini vs GPT-4o few-shot cost-quality tradeoff for JSON extraction
Fine-tune with 500\+ examples when schema has >10 fields and daily volume >10k requests; cost drops from $15/million to $0.20/million tokens with <2% accuracy loss
Journey Context:
GPT-4o costs ~$15 per million tokens \(blended input/output\), while fine-tuned 4o-mini costs ~$0.20 per million. The common mistake is fine-tuning too early with <100 examples, which yields poor accuracy and requires falling back to the large model. The 500-example threshold ensures the fine-tuned model achieves >95% of the large model's accuracy on complex schemas. Volume matters: below 10k requests/day, the $200-500 fine-tuning job cost doesn't amortize over a reasonable payback period.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T13:40:36.436845+00:00— report_created — created