# Q\&A

## What is request cost?

Every API endpoint documentation has the "Request cost formula" section describing how the "cost" is calculated. For most API requests it's always 1. It's more than 1 in cases when you're requiring additional data (e.g. when you're requesting data on an Ethereum address, and you're also requesting its ERC-20 token balances).

{% hint style="info" %}
Example: **Request cost** is $$0 < x \leq 10 \Rightarrow \lim\_{n \to x}1 + (0.1 \* (n - 1))$$&#x20;

You want to send 10 addresses/blocks/transactions:

$$x = 10 \Rightarrow \lim\_{n \to 10}1 + (0.1 \* (10 - 1)) \Rightarrow 1 + (0.1 \* (10 - 1)) = 1.9$$&#x20;

You will have a request cost of **1.9**
{% endhint %}

## How many request are I limit to with the free tier?

You are limitied up to 1440 requests a day. With an API key you could do more than 1440 requests a day

## When do the request counter reset?

The daily request counter is reset at 00:00 UTC every day.


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