Comparison
Offline Evaluation vs Online Evaluation
Offline Evaluation and Online Evaluation are both common AI/LLM terms but cover different ideas. Here is a quick side-by-side.
When you would reach for Offline Evaluation
Offline Evaluation comes up when the question is fundamentally about evaluation.
A RAG team's offline eval: 500 (question, gold answer) pairs, scored by LLM-as-judge on faithfulness and relevance, run on every prompt PR.
When you would reach for Online Evaluation
After offline eval is solid and you have meaningful production volume. Stretch your eval coverage from a fixed set to a live one.
Phoenix running a faithfulness eval on 5% of production RAG traces, dashboard charts the rolling 7-day mean.
Frequently asked
What is the difference between Offline Evaluation and Online Evaluation?
Offline Evaluation: Offline evaluation runs a fixed dataset of inputs through a candidate model or prompt, scores each output, and reports aggregate quality — the standard way to compare changes before shipping. Online Evaluation: Online evaluation runs scoring functions over live production traffic — usually a sample of recent traces — to monitor quality continuously instead of relying solely on a fixed offline dataset.
When should I use Offline Evaluation vs Online Evaluation?
Offline Evaluation is the right concept when you are focused on evaluation. After offline eval is solid and you have meaningful production volume. Stretch your eval coverage from a fixed set to a live one.
Are Offline Evaluation and Online Evaluation the same thing?
No. Offline Evaluation is evaluation; Online Evaluation is evaluation. They are related but address different parts of the AI stack.