Promptfoo vs Traceloop
Updated March 10, 2026
vs
Overview
Rating
10.0 / 10
Rating
10.0 / 10
Best For
—
Best For
Teams already using Datadog/Splunk wanting LLM observability
Product Summary
Promptfoo is an open-source tool for testing and evaluating LLM prompts. It lets developers define test cases, run them against multiple models, compare outputs side-by-side, and catch regressions before deployment. Supports custom scoring functions, red-teaming, and CI/CD integration for automated prompt testing.
Product Summary
The OpenTelemetry standard for AI. Pipes LLM telemetry into Datadog, Splunk, or any OTel backend.
Starting Price
$0Per perpetual
Starting Price
open-source
Free Trial
Yes
Free Trial
No
Free Version
No
Free Version
No
Website
Website
Key features
Core capabilities each platform advertises.
Data not available
- OpenTelemetry
- OpenLLMetry
- Vendor-neutral
- OTel integration
Strengths and tradeoffs
What each tool does well, and the limitations to keep in mind.
Pros
- Completely free and open source (MIT license)
- Fast with quality features like live reloads and caching
- Built-in red teaming and security vulnerability scanning
- Trusted by large companies with strong community
Cons
- CLI-focused creates friction for non-technical users
- Limited observability for complex production agents
- No version control for prompts, data, or metrics
- Offline nature hits ceiling for production scale
Pros
- Acquired by ServiceNow for $60-80M providing strong financial backing and integration opportunities
- Built on OpenTelemetry standards with open-source OpenLLMetry SDK
- Recognized as Gartner Cool Vendor demonstrating industry validation
- One-line code integration for quick setup and deployment
- Enterprise-ready with SOC 2, HIPAA compliance and multiple deployment options
Cons
- ServiceNow acquisition may lead to platform changes, pricing adjustments, or strategic shifts
- Small team of 9 employees may be absorbed into larger ServiceNow organization affecting support
- Limited transparent pricing information following acquisition
- Uncertainty around long-term product roadmap under new ownership
Compare Promptfoo and Traceloop on your own traffic
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 500+ models through one gateway.
10KFree traces/mo
500+Models
5 minSetup