Just another bitcoin toolkit

[seoincorporation]

Bitcoin is freedom, or that's what they used to say... The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool we should be able to take our private keys and be able to build our own transactions localy, and just use a 3rd party service to broadcast our transactions.

And that's why i'm building a Bitcoin Toolkit, it runs locally as a web app, and it's some weird temporary wallet with some useful tools for bitcoin.

and before anyone want to try it let me put this red big warning:

You should never use your private keys on a online service

And now lets talk about the tool.



It can do a lot of Bitcoin related things, you can create address, search for address with balance, create transactions, verify balance, sign transactions... and all that kind of thing that a wallet should let us do with some other cool tools.

You can find the demo version here: https://toolkit.lucky.lat/

And if you want to try it locally (this is the right and secure way) you can download the code here.

https://toolkit.lucky.lat/bitcointoolkit.zip

Give me your feedback, what should i add?

--UPDATE--


Features:

Code:

Bitcoin Toolkit — Feature List

Key Management

Generate cryptographically secure private keys (CSPRNG)
View all 4 address formats from any key: P2PKH (Legacy 1…), P2WPKH (Native SegWit bc1q…), P2SH-P2WPKH (Nested SegWit 3…), P2TR (Taproot bc1p…)
Convert between WIF (compressed/uncompressed), hex, and all address formats
Brain Wallet — derive a key from any passphrase via SHA-256 (educational warning included)
BIP39 Mnemonic — generate 12/15/18/21/24-word seed phrases with optional BIP39 passphrase
HD key derivation via BIP32 across BIP44/49/84/86 paths (Legacy, Nested SegWit, Native SegWit, Taproot)
7 BIP39 wordlists: English, Spanish, French, Italian, Portuguese, Czech, Japanese[/li]

Wallet

Load any private key (WIF or hex) as a live wallet
Multi-wallet session — hold multiple wallets simultaneously, switch between them
Per-address-type balance display (confirmed + unconfirmed)
Real-time balance and transaction fetch via Mempool.space / Blockstream API
Recent transaction history with net flow per tx, block height, and explorer link
One-click address copy

Transactions

Send — friendly send page with auto UTXO coin selection (greedy, largest-first), live fee estimation (Economy/Normal/Fast/Custom), BTC/sats unit toggle, Send Max, dust-change detection (folded into fee), broadcast via Mempool.space or Blockstream
TX Builder — full manual control: custom inputs (UTXOs), multiple outputs, custom fee rate, raw hex output, broadcast via Mempool.space or Blockstream
Supports P2PKH, P2WPKH, and P2SH-P2WPKH signing
Sign & Verify — sign arbitrary messages with the Bitcoin Signed Message standard (recoverable ECDSA), verify signatures against P2PKH / P2WPKH / P2SH-P2WPKH / P2TR addresses, copy-to-verify shortcut

Explore

Key Scanner — generate random keys and check live balances (educational vanity demonstration)
Vanity Generator — mine a Bitcoin address starting with a custom prefix (Web Worker, non-blocking)

Network

Full Mainnet, Testnet 3, and Testnet 4 support across all tools
Network-aware address generation, UTXO fetching, fee estimates, and broadcasting
Testnet faucet links built into the network switcher

UX & UI

Dark / Light theme toggle
Collapsible sidebar navigation with grouped sections
Responsive layout — works on desktop and mobile
Toast notifications, clipboard copy everywhere
Collapsible card sections on all detail pages
Security disclaimer modal on first visit
"Load as Wallet" button from Generator, Brain Wallet, BIP39, and Converter pages
Balance check panel built into every key info view

Security & Privacy

100% client-side — no server, no backend
No analytics, no telemetry, no tracking
Private keys never transmitted anywhere
Uses audited zero-dependency crypto libraries: @noble/curves, @noble/hashes, @scure/base, @scure/bip39, @scure/bip32
Works fully offline once loaded (air-gap friendly)
Downloadable as a zip for offline/self-hosted use

[shadow_warden]

Sweet. It would be great if you will host source code on Github.
It looks like you are displaying wrong addresses formats (BIP44, etc) for BIP39 paths.
https://www.talkimg.com/images/2026/06/02/UjBORq.png

[nc50lc]

Bitcoin is freedom, or that's what they used to say... The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool we should be able to take our private keys and be able to build our own transactions localy, and just use a 3rd party service to broadcast our transactions.

As per the saying "don't trust, verify";
If a self-custodial client/wallet is open-source, verified and compiled by the user, then it doesn't act like a third-party anymore since now trustless because the owner knows how it works under the hood.
Only a few users do this though.

[LoyceV]

The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool

I don't get it: you're saying third party software is not cool, and then come up with more third party software.

we should be able to take our private keys and be able to build our own transactions localy

That's exactly what every wallet does, but in a more convenient way.

[n0nce]

The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool

I don't get it: you're saying third party software is not cool, and then come up with more third party software.

His argumentation for using this over a real wallet indeed does not really hold water, but I do believe that building transactions on an offline, air-gapped device is the most secure way to spend your coins.

We should be able to take our private keys and be able to build our own transactions localy, and just use a 3rd party service to broadcast our transactions.

For me personally, this means working with air-gapped hardware wallets. A great tradeoff between convenience and security.

One could also use a dedicated PC, e.g. booting up Tails on a flash drive that comes with Electrum pre-packaged and work with that, but it'll most likely be less secure than a purpose-built device with minimal operating system and security-focused hardware design.

[n0nce]

I want to know something about Electrum wallet, is it good for long term investment preservation, or is trust wallet better. Many places talk about trust wallet. But which wallet is actually better for long term preservation. And which wallet will be more secure?

Electrum is one of the default, old-school, tried and tested open-source Bitcoin wallet options out there.
You can check out the source code for yourself!

Trust Wallet, to the best of my knowledge, is a multi-coin web extension, so a totally different thing feature-wise and security-wise.
Choosing the right wallet for you depends on lots of factors though, and I recommend first establishing what you need, then doing your own research, and if anything's still unclear, post a detailed question. ('How do I ask a good question?')

In short, if you only care about long-term storage of BTC, steer clear of Trust Wallet.
Either buy a trusted, open-source, verifiable, air-gapped hardware wallet and send the funds there, or do the following manual process.

• Create a fresh seed on a machine without antennas or Ethernet running Tails from a USB drive, which comes with Electrum preinstalled.
• Back up the seed onto metal.
  
• Send your funds to one of the addresses.
• Shut down the machine.

Once you need to spend, either go back into Tails and import the seed, or buy a hardware wallet and import the seeds there.
In the Tails method, you will need to put the signed transaction on another storage media, then import it on a computer with internet access and broadcast it to the Bitcoin network.

Unless it already exists, I can make a guide on this process.

[seoincorporation]

Sweet. It would be great if you will host source code on Github.
It looks like you are displaying wrong addresses formats (BIP44, etc) for BIP39 paths.

to see all the address formats you neet to click on:

show all formats > addresses.



But i still get the bug, texts are wrong there, i will fix it, thanks.

I know is not on github, but anyone can download the zip and modify it as they want.

Bitcoin is freedom, or that's what they used to say... The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool we should be able to take our private keys and be able to build our own transactions localy, and just use a 3rd party service to broadcast our transactions.

As per the saying "don't trust, verify";
If a self-custodial client/wallet is open-source, verified and compiled by the user, then it doesn't act like a third-party anymore since now trustless because the owner knows how it works under the hood.
Only a few users do this though.

As you say, only a few users do this... But is nice to see that someone get the idea. And is important to mention that wallet is only one of the features, and that's something that i will update on the main post, the features.

The reality is that 99% of the users need a 3rd party software (called wallets) to store and spend their coins. And that's not cool

I don't get it: you're saying third party software is not cool, and then come up with more third party software.

If you own the source code, and run it locally is not a third party anymore, is a service. Not sure if call it an app, maybe the right name is a Web app, you run it locally with apache.

/var/www/html/Bitcoin$ tree
.
├── bitcointoolkit.zip
├── css
│   └── app.css
├── index.html
├── js
│   ├── api.js
│   ├── app.js
│   ├── bitcoin.js
│   ├── pages
│   │   ├── brainwallet.js
│   │   ├── converter.js
│   │   ├── explore.js
│   │   ├── home.js
│   │   ├── keygen.js
│   │   ├── keys.js
│   │   ├── mnemonic.js
│   │   ├── scanner.js
│   │   ├── send.js
│   │   ├── settings.js
│   │   ├── _shared.js
│   │   ├── sign.js
│   │   ├── txbuilder.js
│   │   └── vanity.js
│   └── wallet.js
├── README.md
└── server.php

3 directories, 23 files

we should be able to take our private keys and be able to build our own transactions localy

That's exactly what every wallet does, but in a more convenient way.

They build the transactions for you, they hold your provate keys. And the real problem of this is the updates and the download sources, there are a lot of cloned wallets with malware outside, and a update could have some encripted malwares as an inside job, is something complex.

This is not a wallet, is a toolkit, with some cool toys, i hope you can see it that way, and if you found something to make it better i will appreciate your feedback.

[nc50lc]

As per the saying "don't trust, verify";

As you say, only a few users do this... But is nice to see that someone get the idea. And is important to mention that wallet is only one of the features, and that's something that i will update on the main post, the features.

But, your tool falls into that category as well.
If the user didn't verify your code, then they're just trusting it to do what you told them what it can do.

So, overall, it's how you define "third-party" here.
Is it for "custodial wallets" or open-source "self-custodial" ones? Because the latter isn't any different from this tool. (as mentioned by Loyce)
Anyways if you agree, while you're updating the OP, rephrasing the claim in the OP that generalized wallets as third-party into specific to "custodial wallets" may be a good idea.

[LoyceV]

If you own the source code, and run it locally is not a third party anymore, is a service.

I can download and compile Bitcoin Core's or Electrum's source code, but that doesn't make it less of third party software. Not many people have the time and skills to check all code they run.

we should be able to take our private keys and be able to build our own transactions localy

That's exactly what every wallet does, but in a more convenient way.

They build the transactions for you, they hold your provate keys.

Who is "they" in this? I hold my private keys, nobody else.

And the real problem of this is the updates and the download sources, there are a lot of cloned wallets with malware outside, and a update could have some encripted malwares as an inside job, is something complex.

None of that changes if I download your software. If you have to "talk down" established wallets to promote your own software, that's not a good start.

[n0nce]

If you own the source code, and run it locally is not a third party anymore, is a service.

99% of the users need a 3rd party software (called wallets) to store and spend their coins.

Now this is a really odd definition. Then anyone who compiles Bitcoin Core, Electrum or Sparrow themselves, is not using a 3rd party software anymore. Actually, they're not even using a wallet anymore!

And the real problem of this is the updates and the download sources, there are a lot of cloned wallets with malware outside, and a update could have some encripted malwares as an inside job, is something complex.

You should compare apples to apples: anyone downloading a cloned version of your software package, bundled with malware, would be equally affected by your described attacker model. Just because your software may show intermediary steps of the transaction set up, there is no way for a human to verify that it is doing the right thing.
In fact, known attacks are built such that an affected user typically doesn't even see a change in the recipient's address; the correct one is shown on screen, but a different address is used for the construction of the transaction briefly before it's broadcast.
Unfortunately, your toolkit does not provide any security improvement against the described attacker model.

If we assume that users may inadvertently install a fake / hacked wallet software, the only remedy is either them having to read through every single line of code and compiling it themselves, or using a hardware wallet with a display for verifying the transaction parameters.

[seoincorporation]

If you own the source code, and run it locally is not a third party anymore, is a service.

I can download and compile Bitcoin Core's or Electrum's source code, but that doesn't make it less of third party software...

But there is a difference between those wallets and my toolkit when we talk about the wallet feature. And is the way that they work.

They broadcast the transactions on their nodes... i use a thirdparty to broadcast the transaction. So, the wallet feature isn't connected to any Bitcoin Node.

Have you girls and guys ever built a transaction manually on bitcoin node? You had to create, sign, and broadcast the transaction... this tool creates and signs the transaction, and you have a transaction ready to broadcast when you want on any online broadcast services.

[nc50lc]

Have you girls and guys ever built a transaction manually on bitcoin node? You had to create, sign, and broadcast the transaction... this tool creates and signs the transaction, and you have a transaction ready to broadcast when you want on any online broadcast services.

Yes, we can create and sign the transaction and skip the broadcast part, through the GUI or commands, offline or online.
Then just like your tool, broadcast it elsewhere.

And the best thing for a node is: If it's the reference client or similar, it's open-source, has reproducible builds and the blockchain is locally verified (not by a third-party)
So skipping the third step isn't even necessary if it's a full node.
On the contrary, broadcasting it on any third-party online broadcast service is worse.

[LoyceV]

I can download and compile Bitcoin Core's or Electrum's source code, but that doesn't make it less of third party software...

But there is a difference between those wallets and my toolkit when we talk about the wallet feature.

I can use Bitcoin Core or Electrum with or without wallet. You seem to be looking for a problem for the solution you've created, but that problem doesn't exist.

They broadcast the transactions on their nodes... i use a thirdparty to broadcast the transaction. So, the wallet feature isn't connected to any Bitcoin Node.

My node broadcasts my transaction to many other nodes, which broadcast it to others again. That's how Bitcoin works. If I use coinb.in to broadcast my transaction, it'll still show up in my own node in about 2 seconds.

Have you girls and guys ever built a transaction manually on bitcoin node? You had to create, sign, and broadcast the transaction...

When you say "manual", I'm thinking of Mining Bitcoin with pencil and paper. Separating the transaction creation process into 3 different steps doesn't make it manual.

this tool creates and signs the transaction, and you have a transaction ready to broadcast when you want on any online broadcast services.

I've done that offline in Electrum many times. The 2 basic rules I follow for keeping things safe, are keeping it offline when needed and using only well trusted software.

[seoincorporation]

I get your point guys, and i'm not looking to compete with softwares like bitcoin core or electrum... The transaction thing is just a feature of my tool, and is important for the bitcoin ecosystem. I just a nice toy for me and want to share it with the community, if any one feels the code is usefull to any other project, then feel free to take it.

I would like to read some positive feedback, don't tell me why it will not work, tell me what you would like to see on this tool.