Bitcoin Wallet: Native SegWit, BTC Fees and RBF Explained

How native SegWit (bc1q) addresses work

Keylo gives you a native SegWit address, also called Bech32 or P2WPKH, derived on the standard BIP84 path m/84'/0'/0'/0/0. It starts with bc1q, is 42 characters long and uses only lowercase letters and digits, so it is easier to read out and its built-in checksum catches most typos. SegWit inputs also weigh less than older formats, which means spending from this address costs less in fees.

You will still see other formats. Addresses starting with 1 are legacy (P2PKH), those starting with 3 are script addresses often used by exchanges and multisig setups, and bc1p addresses are Taproot. They all live on the same Bitcoin network and can pay one another. What matters is that the address belongs to Bitcoin mainnet, not to a test network or a different chain.

Bitcoin also has no account balance in the bank sense. Your balance is the sum of unspent outputs (UTXOs), the separate chunks of BTC you have received. When you send, the wallet gathers enough of them to cover the amount and fee and returns the remainder to you as change. Many tiny UTXOs make a transaction bigger and pricier, and outputs below 546 satoshis count as dust that nodes refuse to relay.

How to create a Bitcoin wallet with Keylo

Keylo's servers only keep the encrypted copy of your wallet and never see your password, phrase or private keys, so Keylo cannot move your bitcoin or restore it for you. If you forget your password, the phrase is the only way back after a reset. Already have a phrase from another wallet? You can import a 12- or 24-word phrase. Wallets that use the same BIP84 native SegWit path will show the same address; older wallets on legacy or nested SegWit paths will not.

1. 1

   Go to create a wallet in any modern browser on your phone, tablet or computer. There is no extension or app to install.

2. 2

   Enter your name, email, phone number and a strong password, then confirm your email from the message Keylo sends.

3. 3

   Keylo generates a standard 12-word recovery phrase in your browser and encrypts it there with a key derived from your password (Argon2id and AES-256-GCM).

4. 4

   Open Bitcoin in your asset list. Your bc1q address is shown with the network name beside it.

5. 5

   Go to Settings, re-enter your password to reveal the phrase, and write it down on paper. Store it somewhere offline.

How to receive BTC

One confirmation takes ten minutes on average, but blocks arrive randomly, so a gap of thirty minutes is not unusual. Exchanges and merchants often wait for one to six confirmations before they treat a payment as final. For larger amounts it is sensible to wait for several confirmations yourself before acting on the money.

1. 1

   Open Bitcoin in Keylo and tap Receive.

2. 2

   Copy your bc1q address or show the QR code to the person or exchange paying you.

3. 3

   Ask them to send on the Bitcoin network itself, usually labelled BTC or Bitcoin.

4. 4

   Watch Activity. The payment shows up once it is broadcast and confirms when a miner includes it in a block. Each entry links to mempool.space.

How to send bitcoin

A confirmed Bitcoin payment cannot be reversed by anyone, including Keylo. Before you confirm, compare the whole address with the one the recipient gave you rather than just the first few characters, because clipboard malware can quietly swap a copied address for an attacker's. If you are paying someone new, a small test payment costs one extra fee and can save a lot of grief.

1. 1

   Open Bitcoin and tap Send.

2. 2

   Paste the recipient's address or scan their QR code. Keylo checks the address checksum before you can continue.

3. 3

   Enter the amount in BTC, or tap Max to send your whole balance minus the network fee.

4. 4

   Choose slow, normal or fast. Each speed is a fee rate in sats/vB.

5. 5

   Review the summary, which shows the exact amount, the recipient and the network fee.

6. 6

   Confirm. Keylo signs the transaction in your browser and broadcasts it.

Bitcoin fees explained: what sats/vB means

Bitcoin fees do not depend on how much BTC you send. They depend on the transaction's size in virtual bytes (vB) multiplied by a fee rate in satoshis per vbyte, where one satoshi is 0.00000001 BTC. A typical native SegWit payment with one input and two outputs is about 141 vB, so at 5 sats/vB it costs roughly 700 satoshis, whether you are moving a small amount or a large one.

The rate is set by competition for block space. Miners fill each block with the best-paying transactions in the mempool, so fast rates climb when demand spikes, while on quiet days a low rate still confirms within an hour or two. Recent Bitcoin Core versions relay rates below 1 sat/vB by default, but not every node has upgraded, so very cheap transactions can be slow to spread.

Size grows with every input. Spending a wallet that received dozens of small payments costs more than spending one large UTXO, which is why fees can look high after many small deposits. Every satoshi of the fee goes to the miner who includes your transaction; Keylo adds nothing to a normal send.

How to speed up a stuck Bitcoin transaction with RBF

If you picked a low rate and the mempool filled up, a payment can sit unconfirmed for hours. Replace-By-Fee (RBF) fixes that. Keylo supports RBF on Bitcoin: it broadcasts a new version of the same payment, spending the same coins at a higher fee rate. Miners prefer the better-paying version, and once it confirms the original becomes invalid. The recipient and amount stay the same; only the fee rises.

A replacement has to pay a higher total fee and a higher rate than the original, plus a little extra to cover relaying it. Bitcoin Core now accepts replacements of any unconfirmed transaction by default, so most nodes pass them on. Once a transaction has a single confirmation it is final and can no longer be replaced.

Swap or bridge BTC to other networks

Keylo includes in-wallet swaps for Bitcoin through decentralized routing. THORChain swaps native BTC directly for coins such as ETH, LTC or DOGE without wrapped tokens, and LI.FI can route BTC into assets on EVM networks through audited bridges. Before you confirm, the quote shows the route, expected output, minimum received and every fee. You can track the transfer until it lands. See swap and bridge for how routing works.

Cross-chain swaps from Bitcoin wait for Bitcoin confirmations before the other side pays out, so expect them to take longer than a normal send. If a route cannot complete, the protocol refunds the sending wallet, less any network fees already spent. A swap may include a small service fee, and it is always listed in the quote rather than hidden in the rate.

Practice with Bitcoin Testnet4 and Signet

Turn on Testnet mode in Settings to add Bitcoin Testnet4 and Bitcoin Signet to your wallet. Both use tb1q addresses and coins with no value that you can get from public faucets. They are a good place to practise sending, choosing a fee rate and bumping a fee with RBF before you touch real BTC. Test coins cannot be exchanged for real bitcoin, so anyone selling them is running a scam.

Bitcoin safety tips

• Write your 12-word recovery phrase on paper or metal and keep it offline. Whoever has it controls your BTC and every other chain in the wallet.
• Never share your password or phrase. Keylo staff will never ask for them, and support can help without them.
• Turn on two-factor authentication and set an anti-phishing code so you can spot fake Keylo emails. How Keylo protects your funds explains each setting.
• Check the full address before every send. Clipboard malware and look-alike addresses rely on people checking only the first and last few characters.
• Ignore anyone who asks for BTC to unlock a prize, investment or recovered funds. Bitcoin payments are final and these offers are always scams.
• Do not use your Keylo address to receive Ordinals inscriptions or Runes. Keylo treats every output as plain BTC, so a later send could spend them.
• Review the session list now and then and log out devices you no longer use.

Frequently asked questions