Best LLM Cost Monitoring Tools in 2026
Top tools for tracking and optimizing LLM API spend across model providers.
We evaluated the leading options for spend firewall in 2026 based on feature depth, pricing transparency, ease of setup, and fit for real-world workflows. Here's our shortlist.
1. sipi.bot
Agent spend firewallPurpose-built circuit breaker with per-agent caps.
Best for: Teams running autonomous agents
2. Helicone
LLM proxyOpen-source proxy with cost dashboards.
Best for: Self-hosters
3. LangSmith
TracingLangChain's tracing and cost platform.
Best for: LangChain teams
4. Portkey
GatewayMulti-model gateway with cost routing.
Best for: Multi-provider teams
How we evaluated
Each option was assessed on four criteria: (1) depth of features for the specific spend firewall use case, (2) pricing model and transparency, (3) time-to-value and onboarding friction, and (4) real-world usability across team sizes. Options that scored well on breadth but poorly on the specific spend firewall workflow were ranked lower.
Related resources
Comparison table
| Feature | sipi.bot | Helicone | Portkey | LiteLLM |
|---|---|---|---|---|
| Real-time spend blocking | ✅ Yes | ❌ | ❌ | ❌ |
| Cost dashboards | ✅ Yes | ✅ Yes | ✅ Yes | ✅ Yes |
| Per-agent budgets | ✅ Yes | ⚠️ Per-key | ⚠️ Per-key | ⚠️ Per-key |
| Spend anomaly detection | ✅ Yes | ⚠️ Post-hoc | ⚠️ Post-hoc | ⚠️ Post-hoc |
| Open source | ✅ MIT | ✅ Apache 2.0 | ✅ MIT | ✅ MIT |
| Works beyond LLMs | ✅ Any spend | ❌ | ❌ | ❌ |
Our pick
Monitoring tells you what happened. sipi.bot controls what happens next. For teams that need both visibility and control, the best setup is Helicone or Portkey for dashboards plus sipi.bot as the guardrail. Most "cost monitoring" tools are passive observers — sipi.bot is the only one that actively prevents overspend before it hits your bill.