---
title: Introduction
description: What Hexkit is and what you can do with it.
url: https://pr-1-9bee85ef9c41.thally.app/
---

# Introduction

What Hexkit is and what you can do with it.

Hexkit is a browser toolkit for working with EVM transactions. Paste a transaction
hash and see what it actually does. Simulate a transaction before you sign it. Read
contract storage, diff a contract upgrade, or step through execution. And put idle
funds into yield vaults across 20+ protocols, including from a chain you don't hold
them on.

It runs entirely in your browser at
[web3-toolkit.vercel.app](https://web3-toolkit.vercel.app) — no install, no account,
no keys handed over. Connect a wallet only when you want to sign something.

#### [Quickstart](/quickstart)

    Decode your first transaction in under a minute.

#### [Simulate a transaction](/guides/simulate-a-transaction)

    See what a transaction does before you sign it.

#### [Decode calldata](/guides/decode-a-transaction)

    Turn a hex blob into a readable function call.

#### [Troubleshooting](/troubleshooting)

    What each error means.

## What's in it

**Decode and identify** — turn raw calldata into readable calls
([Decoder](/guides/decode-a-transaction)), identify unknown selectors and event topics
([Signature Database](/guides/signature-lookup)), and teach it about your own
contracts ([Custom signatures](/guides/custom-signatures)).

**Simulate** — run a transaction against forked chain state without broadcasting it
([Simulator](/guides/simulate-a-transaction)), then read
[what moved](/guides/asset-changes), [what storage changed](/guides/state-changes),
and the [call-by-call trace](/guides/execution-trace) — or
[step through it line by line](/guides/debugger).

**Inspect contracts** — read [verified source](/guides/explore-contract-source),
[compare two deployments](/guides/compare-bytecode), and
[read live storage](/guides/inspect-storage) decoded to variable names.

**Interact** — [call any contract](/guides/call-a-contract), reading without a wallet
and writing with one.

**Earn** — browse yield vaults and [deposit](/guides/deposits) or
[withdraw](/guides/withdrawals), including across chains.

## A note on cross-chain

When you deposit into a vault on a chain you don't hold funds on, Hexkit doesn't
bridge your tokens the usual way. It escrows them on your chain and lets a third
party deliver the tokens on the destination chain, then claims the escrow by proving
they did.

In practice that means one signature instead of several, and a four-step timeline
showing where your money is. It also means there are deadlines, and a way to get your
funds back if nobody completes the job. [How cross-chain works](/concepts/intent-orders)
explains it properly.

> **Note:**
  Hexkit helps you inspect and construct transactions. It is not financial advice.
  Simulate before you sign, and check that the asset changes match what you expect.