A/B Test Designer
Design prompt A/B tests and variations for LLM evaluation
Prompt Variations
Test Inputs
Related Tools
BLEU & ROUGE Calculator
Calculate standard text generation metrics between reference and hypothesis
Confusion Matrix Visualizer
Generate and analyze confusion matrices for classification models
Evaluation Harness Config
Generate configuration files for LM Evaluation Harness
Human Eval Form
Create grading rubrics and forms for human evaluation of LLM outputs
Latency Benchmark Recorder
Record and visualize latency metrics from your own API tests
What is A/B Testing for LLMs?
A/B testing for LLMs compares different prompt variations to find which produces better outputs. By systematically testing multiple system prompts against the same inputs, you can optimize prompt engineering decisions with data rather than intuition.
This tool helps you design test matrices—all combinations of prompt variations and test inputs—that you can then run manually or programmatically against your LLM of choice.
How It Works
1. Define Variations
Create named prompt variations with different system prompts (e.g., formal vs casual, verbose vs concise).
2. Add Test Inputs
Provide representative user prompts that exercise the behaviors you want to test.
3. Generate Matrix
Create all variation x input combinations. Export as CSV and run through your LLM pipeline.
What to Test
- Tone variations: Formal vs casual, professional vs friendly
- Verbosity: Concise responses vs detailed explanations
- Persona: Expert vs beginner-friendly, industry-specific
- Constraints: Step-by-step format vs free-form
FAQ
Does this tool call LLM APIs?
No. This is a planning tool. It generates test matrices you can export and run through your own LLM infrastructure.
How many test cases should I create?
Start with 3-5 variations and 5-10 inputs. As you narrow down, test winning variations more extensively.