> For the complete documentation index, see [llms.txt](https://docs.whatsonchain.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.whatsonchain.com/readme.md).
# Introduction
This API accompanies the [WhatsOnChain.com](https://whatsonchain.com/) website to form a suite of blockchain explorer services that are run on fully independent infrastructure.
## Overview
WhatsOnChain provides access to **BSV** and **BTC** blocks, transactions, address activity, on-chain data, stats, insights, and much more via a simple REST API.
You can also use this API to broadcast transactions to the BSV network.
The supported networks are:
* Mainnet
* Testnet (BSV-only)
[](https://app.getpostman.com/run-collection/40021525-99dd8ca6-9938-4bf1-bc69-7755aab96585)
## Authentication
At this stage no authentication is required to use the API up to 3 requests/sec. If you need more, see below on how to increase your rate limit using an API key.
## Rate Limits
Up to 3 requests/sec is free. Need more? Please create a free account on the WhatsOnChain Platform and view the [available subscription plans](https://dashboard.whatsonchain.com/pricing) there. We offer packages with 10, 20 or 40 requests/sec, and even a custom Enterprise plan.
If you are using the API for free, without an API key, please help us spread the word and use the ["Powered by WhatsOnChain" logo](https://whatsonchain.com/assets#powered-by-whatsonchain) in your app or on your website.
Once you get your API key from the Platform, here is a usage example:
```
curl -H 'Authorization: mainnet_xxxxxxxxxxxxxxxxxxxxxxx' \
https://api.whatsonchain.com/v1/bsv/main/chain/info
```
Please make sure to replace `mainnet_xxxxxxxxxxxxxxxxxxxxxxx` with your actual API key.
If you need higher rate limits on `testnet`, please contact us through [Support](#support).
## Support
Need help? Join our [WoC devs Telegram channel](https://t.me/joinchat/FfE6-EjZhoTHwhDhZH6F-w) and ask anything you need!