Best LLM Proxy for Node.js in 2026: npm-Native Options Compared

If you are building with Node.js and need to route requests to multiple LLM providers, track costs per request, and handle fallbacks automatically, you need an LLM proxy. The question is which one fits your stack. In 2026, there are real npm-native options that install like any other package, no Python, no Docker, no separate infrastructure to manage.

This post compares the top options for Node.js developers, covers what actually matters when picking one, and shows you how to get started in under five minutes.

Why Node.js Developers Need an LLM Proxy

The raw OpenAI or Anthropic client works fine for prototypes. Production looks different. Three problems come up every time:

Cost visibility. Without a proxy, you find out what you spent at the end of the month. By then, a misconfigured agent or a spike in traffic has already run up the bill. You need per-request cost data, in real time, before the invoice.

Model routing. Not every request needs GPT-4o or Claude Opus. Simple classification calls and short completions can go to cheaper models like Haiku or GPT-4o-mini at a fraction of the cost, with no perceptible quality difference. Routing by complexity is something you want at the infrastructure level, not scattered across your application code.

Provider fallback. When Anthropic has an outage or OpenAI rate-limits your key, you want automatic fallback to another provider, not a 500 that wakes you up at 2am. That logic belongs in a proxy, not in every service that calls an LLM.

What to Look for in an npm LLM Proxy

For Node.js projects specifically, the criteria that matter most:

• npm install, no pip or Docker. If the proxy requires a Python runtime or a running container, it does not fit a standard Node.js workflow. You want npm install and done.
• Node.js native. Proxies built on Python or Go work fine in isolation, but they add friction for Node.js teams. Native means the config file is JSON or TypeScript, the CLI follows Node conventions, and the package ships with proper types.
• Per-request cost tracking. Aggregate monthly totals are not enough. You need cost data per request so you can attribute spend to features, users, or agent runs.
• No Docker required for local development. Docker is fine in CI. It is friction in local development. A proxy that starts with one terminal command, no daemon required, is meaningfully easier to adopt.

Top LLM Proxy npm Packages Compared

Here is an honest comparison of the main options available to Node.js developers in 2026. All four have npm packages; the differences are in what each one actually does.

Portkey is a strong option if you want a managed cloud dashboard and do not mind your telemetry going to their servers. Helicone is built primarily around their cloud observability platform; the npm package is a convenience wrapper. llm-proxy is a lightweight open-source package that forwards requests but does not track costs. RelayPlane is the only one that is fully local, Node.js native, and does per-request cost tracking without sending data to a third-party service.

Why RelayPlane Works Best for Node.js-Native Setups

@relayplane/proxy is built specifically for the Node.js developer experience:

No Docker, no Python. The proxy runs as a Node.js process. Install it globally or as a dev dependency, run one command, and it is ready. No daemon, no container, no second terminal managing infrastructure.

MIT licensed. You can inspect everything, fork it, or vendor it into your project. No questions about what is going over the wire.

Per-request cost tracking with maintained pricing tables. Every request gets a cost estimate logged to a local SQLite database. The pricing tables cover 11 providers and are updated with package releases, so you are not maintaining hardcoded token prices.

Compatible with Claude Code, Cursor, and OpenClaw. If you use AI coding tools, routing their requests through RelayPlane gives you visibility into exactly how much each tool costs per session and per day.

Local dashboard included. Open http://localhost:4100 and you get spend charts, model distribution, latency, and error rates. No account required, no data leaves your machine.

Quick Start: 3-Line Setup

Install globally and initialize a config:

npm install -g @relayplane/proxy
relayplane init
relayplane start

Then point your existing OpenAI or Anthropic client at the local proxy. No other code changes:

import OpenAI from 'openai';

const client = new OpenAI({
  baseURL: 'http://localhost:4100/v1',
});

const response = await client.chat.completions.create({
  model: 'gpt-4o',
  messages: [{ role: 'user', content: 'Hello' }],
});

// Cost, tokens, latency — all logged automatically

The proxy intercepts the request, routes it to the right provider, logs the cost, and returns the response. Your application code does not change.

To check your spend in the terminal without opening the dashboard, run relayplane stats.

The Bottom Line

For Node.js developers who want an LLM proxy that installs with npm, runs without Docker, and tracks costs at the request level, the options in 2026 are real and usable. If you are routing to a single provider and just want forwarding, llm-proxy works. If you want a managed cloud dashboard, Portkey is worth evaluating.

If you want a fully local, MIT-licensed proxy with per-request cost data, complexity routing across 11 providers, and compatibility with Claude Code and Cursor, @relayplane/proxy is the cleanest fit for a Node.js-native stack.

npm install -g @relayplane/proxy

Source and docs at relayplane.com.

Matt Turley is a solo developer building RelayPlane. He writes about AI infrastructure, agent workflows, and building in public.