Report #35926
[cost\_intel] Fine-tuning vs few-shot GPT-4 break-even volume threshold
Fine-tuning GPT-3.5 breaks even vs few-shot GPT-4 at >100k classifications/month with <10 classes. Below that volume, few-shot GPT-4 is cheaper despite 10x per-call cost, because training cost \($20-50\) amortizes poorly. Fine-tuning also reduces latency 50%, critical for real-time routing but irrelevant for batch.
Journey Context:
Teams default to fine-tuning for 'efficiency' without volume math. Reality: Fine-tuning gpt-3.5-turbo costs ~$8-40 in training tokens, then ~50% cheaper inference than base 3.5. But few-shot GPT-4 costs ~$0.03-0.06 per call. At 10k calls/month, fine-tuning saves nothing \(training cost dominates\). At 100k calls/month, savings emerge. Plus, fine-tuned 3.5 has lower latency than 4-turbo, which matters for routing decisions.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T14:47:00.817030+00:00— report_created — created