Ian Coleman BIP39 Tool is a free, open-source utility for experienced users who want to see which Bitcoin addresses and private keys a BIP39 seed phrase produces. It is meant for people who already understand how wallet keys work and want to check their own phrases on a computer that stays offline. The official Windows version is available.
Before you start, note that the most recent code update dates to August 2023, more than two years ago. The project is MIT-licensed, so the code stays open for review, but it has seen no code changes since that update. Treat it as a narrow, specialized tool, and read the safety section before you enter any real seed phrase.
What Is a BIP39 Mnemonic?
A BIP39 mnemonic is a sequence of common English words that encodes the randomness behind a crypto wallet. Wallet software turns that sequence into a seed, and the seed becomes the root from which many keys are derived. Because words are easier to write down than long hexadecimal strings, they became the standard backup format for hierarchical deterministic wallets.
The same phrase always produces the same keys, which is why it is so valuable. Anyone who sees the phrase can reconstruct the wallet, so it should be treated like a master password rather than an ordinary note. A tool like this one shows you what a phrase generates, but it does not replace secure storage. Understanding this model makes it clearer why offline handling matters, and why a single typo in a backup can make it unusable.
Who Is This Tool For?
The tool suits people who already manage their own keys and want to verify a phrase before trusting it. A common case is checking that a paper backup reproduces the address you expect, since a transcription error can quietly make a backup useless. Another case is studying how seed phrases map to addresses, for example during a course or while building your own wallet software.
It is a poor fit for someone who has never handled a private key. Newcomers are better served by a maintained wallet application that handles derivation automatically. Expect to spend time reading the settings, and expect that the interface assumes you already know what a derivation path is. Careful, slow use suits this tool far better than a quick, casual check.
How a Seed Phrase Becomes Addresses
Conversion happens in stages. First the words are checked against the BIP39 word list and a checksum, which catches many typing mistakes. The phrase is then processed into a seed. From that seed, a master key is created, and a derivation path made of account and index numbers selects the branch that leads to a specific key.
Each private key is turned into a public key and then into an address using rules that depend on the network. Bitcoin addresses follow Bitcoin's own formats. Because the path decides which keys appear, a wallet that uses a different path will show different addresses for the same words. That is why the derivation path setting matters even when the defaults work well.
Key features
Phrase to address conversion
Offline operation
Adjustable derivation path
Open source under MIT
Supported coins
The documentation refers to Bitcoin (BTC) as the network the tool handles. Address formats and derivation paths differ between blockchains, so check that the output matches the wallet you are restoring before you send any funds. Do not assume support for other networks; confirm it against the official materials first.
How to install Ian Coleman BIP39 Tool on Windows
- 1
Download from the official source
Download only from the official website or from the project's GitHub Releases page at github.com/iancoleman/bip39. Choose the official Windows version and note the version number, which is 0.5.6 at the time of writing. Avoid mirror sites, bundled installers and links shared in chat groups.
- 2
Verify the file
Before you run anything, compute the SHA-256 checksum with PowerShell using Get-FileHash, then compare the result with the value published alongside the release. If a signature is provided instead, verify it with the tools your system supports. Do not run a file whose hash does not match.
-
Prepare an isolated computer
Install the tool on a machine you can keep disconnected from the internet, or use a session with networking turned off. Extract the files to a folder, launch the program, and confirm the network connection is off before you enter any phrase.
System requirements
- Windows, with the official Windows version available for download
- A computer that can stay disconnected from the internet while the tool runs
How to use Ian Coleman BIP39 Tool
Set up the session before you open the tool, because every step depends on keeping the phrase off networked devices. Work through the sequence below each time, and clear the screen when you finish.
- Disconnect the computer from the internet and close any browser windows.
- Launch the tool and enter your BIP39 mnemonic, checking each word against your backup.
- Work with Bitcoin (BTC), the network the documentation covers.
- Leave the derivation path at its default unless the wallet you are restoring uses a different one. Changing it produces entirely different addresses.
- Review the addresses and private keys shown, and compare the first address with the one your wallet displays.
- Copy only what you need, then clear the clipboard and close the tool.
- Restart or power down the computer before reconnecting it to the internet.
The comparison in step 5 is the most valuable check. If the addresses match, the phrase and path are consistent with that wallet. If they do not, look for a typo or a path mismatch before assuming anything else.
Pros & cons
- Free to use and released under the MIT license
- Designed to run offline, keeping conversions off networked devices
- Derivation path defaults are usable for most common setups
- Open source, so the code can be reviewed
- The most recent code update was in August 2023, more than two years ago
- Documentation mentions Bitcoin (BTC) only
- Security depends entirely on the computer and environment you run it in
- Assumes you already understand seed phrases and derivation paths
Is Ian Coleman BIP39 Tool safe?
Treat this tool as high-risk software, because it handles the secret that controls your funds. The last code update was in August 2023, more than two years ago, so review the project status before use. Download only from the official website or the GitHub Releases page, and compare the SHA-256 checksum or signature of the file with the published value before running it. Run the tool on an isolated computer with no internet connection. Never enter a seed phrase on a third-party website, including any page that offers an online version of this tool. Check the latest version on the official website before you rely on it.
- Official source only. Download from github.com/iancoleman/bip39. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Most tools in this catalog serve different purposes. VanitySearch and Vaniton generate Bitcoin and TON addresses that match chosen patterns, so they create new keys rather than reading an existing phrase. Galvanity and Cosmosvanity do similar generation work for Algorand and Cosmos. John the Ripper targets forgotten wallet passwords, and PaperVault focuses on printable encrypted backups using Shamir's Secret Sharing, which is about storage rather than verification. Ian Coleman BIP39 Tool is narrower. It takes a phrase you already have and shows what it derives, so choose it for checking, and choose the others for generation, recovery or storage.
Specifications
- Price
- Free
- Type
- Open source
- License
- MIT
- Latest version
- 0.5.6
- Last update
- 1 Aug 2023
- Windows support
- Yes (official Windows version)
- Source code
- github.com/iancoleman/bip39
Frequently asked questions
It can be used safely with precautions, because it is open source under the MIT license and designed to run offline. Safety depends on where you download it, whether the file matches its checksum, and whether you run it on a computer without internet access. Its last code update was in August 2023, so weigh that age before entering any real seed phrase.
It converts a BIP39 mnemonic phrase into addresses and private keys. You enter the words, adjust the derivation path if needed, and the tool displays the results. People often use it to confirm what a phrase controls, such as checking a paper backup before relying on it.
Yes, the tool is free and released under the MIT license. That license lets you read, copy and modify the source code. Free use does not mean active maintenance, so look at the project page on GitHub for recent activity before depending on it.
The documentation mentions Bitcoin (BTC), so that is the network to focus on. Address formats and derivation paths differ between blockchains, so confirm that the output matches your wallet before sending any funds. Do not assume support for other networks without checking the official materials.
No. The tool is designed as an offline utility, and the sensible way to use it is on an isolated computer with networking disabled. Keeping the connection off reduces the chance that a phrase is exposed to remote software while you work.
Usually not. The default path is usable for many setups, and changing it produces different addresses. Change it only when the wallet that created your phrase uses a specific path, and check that path in that wallet's own documentation.
Verdict
Ian Coleman BIP39 Tool is a narrow, free utility for people who already know their way around seed phrases. It does one job well: turning a BIP39 mnemonic into Bitcoin addresses and private keys on a machine that stays offline. Its MIT license and offline design appeal to careful users. The 2023 code update and documentation that mentions only Bitcoin make it a fit for experienced users checking backups, not for beginners who want a everyday wallet.