OpenRouter routes requests to the best available providers for your model. By default, requests are load balanced across the top providers to maximize uptime.
You can customize how your requests are routed using the provider object in the request body for Chat Completions and Completions.
For a complete list of valid provider names to use in the API, see the full provider schema.
The provider object can contain the following fields:
For each model in your request, OpenRouter’s default behavior is to load balance requests across providers, prioritizing price.
If you are more sensitive to throughput than price, you can use the sort field to explicitly prioritize throughput.
When you send a request with tools or tool_choice, OpenRouter will only
route to providers that support tool use. Similarly, if you set a
max_tokens, then OpenRouter will only route to providers that support a
response of that length.
Here is OpenRouter’s default load balancing strategy:
If Provider A costs $1 per million tokens, Provider B costs $2, and Provider C costs $3, and Provider B recently saw a few outages.
If you have sort or order set in your provider preferences, load balancing will be disabled.
As described above, OpenRouter load balances based on price, while taking uptime into account.
If you instead want to explicitly prioritize a particular provider attribute, you can include the sort field in the provider preferences. Load balancing will be disabled, and the router will try providers in order.
The three sort options are:
"price": prioritize lowest price"throughput": prioritize highest throughput"latency": prioritize lowest latencyTo always prioritize low prices, and not apply any load balancing, set sort to "price".
To always prioritize low latency, and not apply any load balancing, set sort to "latency".
You can append :nitro to any model slug as a shortcut to sort by throughput. This is exactly equivalent to setting provider.sort to "throughput".
You can append :floor to any model slug as a shortcut to sort by price. This is exactly equivalent to setting provider.sort to "price".
You can set the providers that OpenRouter will prioritize for your request using the order field.
The router will prioritize providers in this list, and in this order, for the model you’re using. If you don’t set this field, the router will load balance across the top providers to maximize uptime.
You can use the copy button next to provider names on model pages to get the exact provider slug, including any variants like “/turbo”. See Targeting Specific Provider Endpoints for details.
OpenRouter will try them one at a time and proceed to other providers if none are operational. If you don’t want to allow any other providers, you should disable fallbacks as well.
This example skips over OpenAI (which doesn’t host Mixtral), tries Together, and then falls back to the normal list of providers on OpenRouter:
Here’s an example with allow_fallbacks set to false that skips over OpenAI (which doesn’t host Mixtral), tries Together, and then fails if Together fails:
Each provider on OpenRouter may host multiple endpoints for the same model, such as a default endpoint and a specialized “turbo” endpoint. To target a specific endpoint, you can use the copy button next to the provider name on the model detail page to obtain the exact provider slug.
For example, DeepInfra offers DeepSeek R1 through multiple endpoints:
deepinfradeepinfra/turboBy copying the exact provider slug and using it in your request’s order array, you can ensure your request is routed to the specific endpoint you want:
This approach is especially useful when you want to consistently use a specific variant of a model from a particular provider.
You can restrict requests only to providers that support all parameters in your request using the require_parameters field.
With the default routing strategy, providers that don’t support all the LLM parameters specified in your request can still receive the request, but will ignore unknown parameters. When you set require_parameters to true, the request won’t even be routed to that provider.
For example, to only use providers that support JSON formatting:
You can restrict requests only to providers that comply with your data policies using the data_collection field.
allow: (default) allow providers which store user data non-transiently and may train on itdeny: use only providers which do not collect user dataSome model providers may log prompts, so we display them with a Data Policy tag on model pages. This is not a definitive source of third party data policies, but represents our best knowledge.
This is also available as an account-wide setting in your privacy settings. You can disable third party model providers that store inputs for training.
To exclude providers that don’t comply with your data policies, set data_collection to deny:
To guarantee that your request is only served by the top (lowest-cost) provider, you can disable fallbacks.
This is combined with the order field from Ordering Specific Providers to restrict the providers that OpenRouter will prioritize to just your chosen list.
You can allow only specific providers for a request by setting the only field in the provider object.
Only allowing some providers may significantly reduce fallback options and limit request recovery.
You can allow providers for all account requests by configuring your preferences. This configuration applies to all API requests and chatroom messages.
Note that when you allow providers for a specific request, the list of allowed providers is merged with your account-wide allowed providers.
Here’s an example that will only use Azure for a request calling GPT-4 Omni:
You can ignore providers for a request by setting the ignore field in the provider object.
Ignoring multiple providers may significantly reduce fallback options and limit request recovery.
You can ignore providers for all account requests by configuring your preferences. This configuration applies to all API requests and chatroom messages.
Note that when you ignore providers for a specific request, the list of ignored providers is merged with your account-wide ignored providers.
Here’s an example that will ignore DeepInfra for a request calling Llama 3.3 70b:
Quantization reduces model size and computational requirements while aiming to preserve performance. Most LLMs today use FP16 or BF16 for training and inference, cutting memory requirements in half compared to FP32. Some optimizations use FP8 or quantization to reduce size further (e.g., INT8, INT4).
Quantized models may exhibit degraded performance for certain prompts, depending on the method used.
Providers can support various quantization levels for open-weight models.
By default, requests are load-balanced across all available providers, ordered by price. To filter providers by quantization level, specify the quantizations field in the provider parameter with the following values:
int4: Integer (4 bit)int8: Integer (8 bit)fp4: Floating point (4 bit)fp6: Floating point (6 bit)fp8: Floating point (8 bit)fp16: Floating point (16 bit)bf16: Brain floating point (16 bit)fp32: Floating point (32 bit)unknown: UnknownHere’s an example that will only use providers that support FP8 quantization:
To filter providers by price, specify the max_price field in the provider parameter with a JSON object specifying the highest provider pricing you will accept.
For example, the value {"prompt": 1, "completion": 2} will route to any provider with a price of <= $1/m prompt tokens, and <= $2/m completion tokens or less.
Some providers support per request pricing, in which case you can use the request attribute of max_price. Lastly, image is also available, which specifies the max price per image you will accept.
Practically, this field is often combined with a provider sort to express, for example, “Use the provider with the highest throughput, as long as it doesn’t cost more than $x/m tokens.”
You can view the terms of service for each provider below. You may not violate the terms of service or policies of third-party providers that power the models on OpenRouter.
For a complete list of options, see this JSON schema: