Rate limits are restrictions that we impose on the number of times and tokens a user can access our API services within a specified period of time.

Currently the rate limit for the Voyage Embeddings API is set at 300 RPM (requests per minute) and 1M TPM (tokens per minute), which means that a user or client is allowed to make up to 300 API requests and process at most 1M tokens within one minute. The rate limit for the Voyage Reranker API is set at 100 RPM (requests per minute) and 2M TPM (tokens per minute). Please refer to tokenization for the calculation of the number of tokens. Adhering to this limit ensures a balanced and efficient utilization of the API's resources, preventing excessive traffic that could impact the overall performance and accessibility of the service.

Why do we have rate limits?

Rate limits are commonly adopted in APIs, serving several vital purposes:

Rate limits promote equitable access to the API for all users. If one individual or organization generates an excessive volume of requests, it could potentially impede the API's performance for others. Through rate limiting, Voyage ensures that a larger number of users can utilize the API without encountering performance issues.
Rate limits enable Voyage AI to effectively manage the workload on its infrastructure. Sudden and substantial spikes in API requests could strain server resources and lead to performance degradation. By establishing rate limits, Voyage can effectively maintain a consistent and reliable experience for all users.
They act as a safeguard against potential abuse or misuse of the API. For instance, malicious actors might attempt to inundate the API with excessive requests to overload it or disrupt its services. By instituting rate limits, Voyage can thwart such nefarious activities.

What happens if I exceed the rate limit?

If you exceed the established rate limit, you will encounter an error, specifically receiving an error message with the error code 429.

How can I avoid hitting rate limits?

In this section, we’ll offer some tips to avoid and manage rate limit errors. We will provide code snippets to demonstrate these tips and as a starting point for you to use. The code snippets assume you've properly installed the Voyage AI python package and have a configured API key. You can use the following boilerplate code with all of the provided code snippets.

import voyageai

vo = voyageai.Client()

documents = [
    "The Mediterranean diet emphasizes fish, olive oil, and vegetables, believed to reduce chronic diseases.",
    "Photosynthesis in plants converts light energy into glucose and produces essential oxygen.",
    "20th-century innovations, from radios to smartphones, centered on electronic advancements.",
    "Rivers provide water, irrigation, and habitat for aquatic species, vital for ecosystems.",
    "Apple’s conference call to discuss fourth fiscal quarter results and business updates is scheduled for Thursday, November 2, 2023 at 2:00 p.m. PT / 5:00 p.m. ET.",
    "Shakespeare's works, like 'Hamlet' and 'A Midsummer Night's Dream,' endure in literature."
]

Use larger batches

If you have many documents to embed, you can increase the number of documents you embed per request and increase your overall throughput by sending larger batches. A "batch" is the collection of documents you are embedding in one request, and the "batch size" is the number of documents in the batch, meaning the length of the list of documents.

For example, assume you want to vectorize 512 documents. If you used a batch size of 1, then this would require 512 requests and you could hit your RPM limit. However, if you used a batch size of 128, then this would require only 4 requests and you would not hit your RPM limit. You can control the batch size by changing the number of documents you provide in the request, and using larger batch sizes will reduce your overall RPM for a given number of documents.

The following are a compact code to vectorize documents in batches of size 128, and a more verbose code printing out useful runtime logs.

# Embed more than 128 documents in a for loop.

batch_size = 128
embeddings = []

for i in range(0, len(documents), batch_size):
    embeddings += vo.embed(
        documents[i:i + batch_size], model="voyage-large-2-instruct", input_type="document"
    ).embeddings

# Embed more than 128 documents in a for loop.
# Note: it requires the tokenizers package, which can be installed with `pip install tokenizers`

batch_size = 128
print("Total documents:", len(documents))
embeddings = []

for i in range(0, len(documents), batch_size):
    batch = documents[i:i + batch_size]

    print(f"Embedding documents {i} to {i + len(batch) - 1}")
    print("Total tokens:", vo.count_tokens(batch))

    batch_embeddings = vo.embed(
        batch, model="voyage-2", input_type="document"
    ).embeddings
    embeddings += batch_embeddings
    
    print("Embeddings preview:", embeddings[0][:5])

Finally, you will need to consider the API maximum batch size and tokens when selecting your batch size. You cannot exceed the API max batch size, and if you have longer documents, the token limit per request may constrain you to a smaller batch size.

Set a wait period

Another way to manage rate limit errors is to simply make requests less frequently. This applies to both RPM and TPM. You can do this by pacing your requests, and the most straightforward approach is inserting a wait period between each request.

import time

batch_size = 128
embeddings = []

for i in range(0, len(documents), batch_size):
    batch = documents[i:i + batch_size]
    embeddings += vo.embed(
        batch, model="voyage-large-2-instruct", input_type="document"
    ).embeddings

    # Add a small amount of sleep in between each iteration
    time.sleep(0.1)

Exponential Backoff

One strategy is to backoff once you’ve hit your rate limit (i.e., receive a 429 error). With this strategy, you wait for an exponentially increased time after receiving a rate limit error before trying again. This continues until the request is successful or until a maximum number of retries is reached. For example, if your initial wait time was 1 second and you got three consecutive rate limit errors before success, you would wait 1, 2, and 4 seconds after each rate limit error, respectively, before re-sending the request.

The following code snippet demonstrates how to implement exponential backoff (with a little bit of jitter) in Python using the tenacity package.

# Note: it requires the tenacity package, which can be installed with `pip install tenacity`
from tenacity import (
    retry,
    stop_after_attempt,
    wait_random_exponential,  
)

@retry(wait=wait_random_exponential(multiplier=1, max=60), stop=stop_after_attempt(6))  
def embed_with_backoff(**kwargs):
    return vo.embed(**kwargs)

embed_with_backoff(texts=documents, model="voyage-large-2-instruct", input_type="document")

Request rate limit increase

If the above methods are insufficient for your use case, please let us know and request a rate limit increase.