Compare · AI gateways and routers

Limitr vs LiteLLM.

LiteLLM caps what a key spends at provider prices. Limitr decides what a customer may use against their plan, their contract, and what you charge them.

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The short answer

LiteLLM

Open-source LLM proxy with virtual keys, budgets, and routing.

Limitr

Decides every call in your app, with prices, costs, limits, and contract terms, then bills it.

Side by side

What happens when…

The moments that decide it, answered from each product's own docs and pricing.

When…LiteLLMLimitr

An agent loop runs away at 2 a.m.Budgets per virtual key, team, or user stop spend at the proxy, in provider dollars.The call that would break the budget never runs. Task, customer, and org budgets are checked in your app first.

A customer costs more than they paySpend at provider prices. No revenue, so no margin.Margin per account is live, and a cap on what an account can cost you stops it before it turns unprofitable.

A customer's AI budget runs lowRouting and fallbacks follow providers, not the customer’s plan.Your app asks Limitr which models the customer may use and can afford, and switches or downgrades. No proxy, no token resale.

Billing your customers for AINot a billing tool.Meters each customer, keeps the ledger, and sends invoices. Collect through Stripe, or bill manually.

The service is unreachableEvery model call goes through the proxy.Nothing to reach. Decisions run in your process and keep working offline.

Checked November 10, 2026. Sources: LiteLLM virtual keys · LiteLLM budgets and rate limits. Something out of date? Tell us.

Architecture

Where the decision happens.

The difference most comparisons skip: where a call is allowed, priced, and capped, and when.

LiteLLM

A gateway in the request path

Every call routes through their gateway or proxy, which enforces budgets per key at provider prices.

Your app

every call

Gatewaycaps per key

then

Model or APIthe cost

Limitr

Inside your app, before the call

The engine runs natively in your process and decides every call in about a millisecond: allowed, priced at your cost and your price, and held to the contract. Usage goes to Limitr Cloud in the background.

Your appLimitr engine inside

decided first

Model or APIthe cost

in the background

Limitr Cloudledger and invoices

Proof

Don't take our word for it.

Bring last month's usage. We'll replay it through Limitr Analyst and show your margin per account, and what Limitr would have stopped.

100,000+users metered for The Regis Company's Fortune 500 contract 971 of 1,000attack calls stopped inside the app in our abuse demo, on a real policy 0network calls to decide a request. It keeps deciding when the network doesn't.Apache 2.0Read exactly what decides your calls.

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The gap

What you'd still build on LiteLLM.

Teams pair LiteLLM with code of their own. With Limitr, that part is the product.

With LiteLLM, you still build

With Limitr, you get

Limits tied to plans and contracts

Limits tied to the customer's plan and contract

Revenue next to spend, for margin

Your cost and your price on every call, so margin per account is live

Metering and invoices for your customers

Metering, ledger, and invoices for your customers

Choose LiteLLM, next to Limitr, for one API in front of every model provider.

Using both

Route with LiteLLM, decide with Limitr.

Limitr tells your app what a customer may use and can afford. LiteLLM sends the call to the right provider.

LiteLLM

Provider routing and fallbacks
One API for every model

Limitr

What this customer may use
Pricing and billing each call

Switching

From LiteLLM to Limitr.

No migration day. Limitr runs next to what you have until the numbers match.

Book a replay Map your pricing

Keep LiteLLM for routing to providers.

Run Limitr in observe mode next to LiteLLM and compare the numbers on real traffic.

Switch enforcement on. Customers come over as they appear, with no migration day.

Common questions

Limitr vs LiteLLM, answered.

Yes, by deciding. Your app asks Limitr whether a customer may use a model, or can afford it, and switches to another when the answer is no. Limitr never proxies the call.

LiteLLM caps what a key spends at provider prices. Limitr decides what a customer may use against their plan, their contract, and what you charge them. Choose LiteLLM, next to Limitr, for one API in front of every model provider.

LiteLLM: a gateway in the request path. Every call routes through their gateway or proxy, which enforces budgets per key at provider prices. Limitr: inside your app, before the call. The engine runs natively in your process and decides every call in about a millisecond: allowed, priced at your cost and your price, and held to the contract. Usage goes to Limitr Cloud in the background.

Keep LiteLLM for routing to providers. Run Limitr in observe mode next to LiteLLM and compare the numbers on real traffic. Switch enforcement on. Customers come over as they appear, with no migration day.

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