> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tenderly.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Simulations Overview

> Simulate single or bundled transactions via API or RPC with decoded traces, accurate gas estimates, balance changes, and more.

Transaction Simulations let you predict a transaction's exact outcome before it is executed on the network. Tenderly enables you to run simulations on any of the [102 supported networks](/platform/supported-networks) in one place.

Tenderly simulates transactions in a virtual environment that is a replica of the real blockchain. This ensures you're always getting the most accurate simulation results: **100% accurate gas usage breakdown**, **assets exchanged**, **balance changes**, **storage updates**, and entire **decoded transaction trace**.

<CardGroup cols={3}>
  <Card title="Simulate via RPC" href="/simulations/quickstart#rpc-simulations-quickstart">
    Opt to simulate via RPC when you need combined capabilities of blockchain access and simulations.
  </Card>

  <Card title="Simulate via API" href="/simulations/single-simulations#simulate-via-api">
    Incorporate simulations seamlessly into your dapp or wallet using standard REST endpoints.
  </Card>

  <Card title="Tenderly SDK" href="/platform/sdk/introduction">
    The Tenderly SDK provides useful utilities for quickly adding simulations into your dapp or wallet.
  </Card>
</CardGroup>

See the [supported networks](/platform/supported-networks) for the full list.

## Features

Learn how to simulate single and bundled transactions via API or RPC.

<CardGroup cols={2}>
  <Card title="Single Transaction Simulations" href="/simulations/single-simulations">
    Integrate simulations into your dapp to give users the ability to preview the results of their transactions without risking real assets and or spending money on gas.
  </Card>

  <Card title="Bundled Transaction Simulations" href="/simulations/bundled-simulations">
    Simulate bundled transactions in one go and test the results of all interdependent transactions. Bundled simulations are ideal for governance proposals or strategy testing.
  </Card>
</CardGroup>

## Use cases

* [**Asset and balance changes**](/simulations/asset-balance-changes): Get exact dollar values for all balance and asset changes that will happen.
* [**Gas estimation**](/simulations/gas-estimation): Accurately predict the gas costs before sending the transaction.
* [**State overrides**](/simulations/state-overrides): Modify blockchain conditions like timestamps and contract data to test different scenarios.
* [**Preview transaction outcomes**](/simulations/transaction-preview): Identify and fix issues that could cause transactions to fail.
* **Access lists**: Create lists of addresses and storage slots the transaction will access.
* **Human-readable errors**: Get complex errors decoded into explanations that you can easily understand.

## Resources

<CardGroup cols={3}>
  <Card title="Quickstart" icon="play" href="/simulations/quickstart">
    Learn the quickest way to integrate simulations into your dapp or wallet.
  </Card>

  <Card title="Authentication" icon="key" href="/platform/account/projects/api-tokens">
    Learn how to configure and authenticate access to the API and RPC.
  </Card>

  <Card title="Guides" icon="file-code" href="/simulations/overview">
    Browse our growing library of transaction simulation integration guides.
  </Card>

  <Card title="API Reference" icon="brackets-curly" href="/api-reference">
    Get familiar with all the API simulation endpoints, requests, and parameters.
  </Card>

  <Card title="FAQ" icon="circle-question" href="/troubleshooting/simulations">
    Get answers to the most commonly asked questions about simulations.
  </Card>
</CardGroup>