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Fiddler AI logo
Fiddler AI
✓ verifiedFreemium

Enterprise AI observability and security platform to monitor, evaluate, and govern agentic and ML systems with guardrails.

51K visits/mo
ApX Machine Learning logo
ApX Machine Learning
✓ verifiedFreemium

Tools, model specs and courses for LLM engineers-VRAM calculator, benchmarks and model directory-with free and paid tiers.

355K visits/mo
Helicone logo
Helicone
✓ verifiedFreemium

LLM observability platform and AI gateway that lets teams route, log, debug and analyze their model requests.

100K visits/mo
Openlit logo
Openlit
✓ verifiedFreemium

Open-source, OpenTelemetry-native platform for LLM observability, tracing, evaluation and prompt management.

9.1K visits/mo
Higress logo
Higress
✓ verifiedFreemium

Open-source AI-native API gateway for routing, protecting and caching LLM/agent traffic, with a paid managed cloud.

29K visits/mo
Pricing
Free: $0 (real-time guardrails)
Developer: $0.002 per trace
Basic: $0/mo (free forever)
Pro: $19/mo
Pro+: $59/mo
Hobby: Free (10,000 requests/mo)
Pro: $79/mo (unlimited seats)
Team: $799/mo (SOC-2 & HIPAA)

Free trial available

Self-Hosted: $0 (Apache 2.0, no usage limits)

No public pricing

Core features
  • End-to-end agentic and ML observability
  • Real-time guardrails (hallucination, PII, jailbreak)
  • Continuous evaluations and custom judges
  • Root-cause analysis and decision lineage
  • AI governance, risk, and compliance controls
  • Flexible SaaS, VPC, or on-prem deployment
  • VRAM/GPU-memory calculator for LLMs
  • LLM performance rankings and benchmarks
  • Model directory and comparison
  • AI/ML courses and learning roadmap
  • Calculator API and exportable cost reports
  • Engineering blog and guides
  • Request logging and LLM observability
  • AI gateway with routing and automatic fallbacks
  • Caching and rate limiting
  • Session, user and custom-property analytics
  • Prompts, playground and datasets for testing
  • Integrations with OpenAI, Anthropic, Azure and more
  • OpenTelemetry-native distributed tracing
  • Token usage and cost tracking
  • LLM evaluations (online/offline)
  • Prompt management and versioning
  • GPU and vector-DB monitoring
  • 60+ LLM/framework integrations
  • Self-hostable via Docker; export to Grafana/Datadog
  • Unified proxy and protocol conversion across 100+ LLMs
  • Model-level fallback and routing
  • Semantic and exact-match AI caching
  • Token tracking and quota controls
  • Content-safety and data-protection filtering
  • MCP service hosting and plugin marketplace
Use cases
  • Monitoring production AI agents
  • Enforcing safety guardrails on LLM apps
  • Evaluating and debugging model behavior
  • Governance and compliance for enterprise AI
  • Estimating GPU memory before training or inference
  • Comparing and selecting LLMs
  • Learning ML and LLM engineering
  • Modeling production deployment costs
  • Monitoring and debugging LLM apps
  • Analyzing model usage and cost
  • Caching responses to cut spend
  • Managing prompts and testing datasets
  • Trace and debug LLM applications
  • Monitor AI cost and performance
  • Evaluate prompts and models
  • Add observability without code changes
  • Centralizing access to multiple LLM providers
  • Building and governing AI agent/MCP services
  • Controlling token spend across teams
  • Adding caching and safety to LLM calls
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