BTC Network
Real-time Bitcoin network insights and tools
Bitcoin Fee Calculator
Estimated Fee (BTC)
Estimated Fee (USD)
Transaction Details
Use Segwit
Lower fees with segregated witness
Network Status
Time since last block
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Unconfirmed transactions
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Mempool size
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Current optimal fee
2.5 sat/vB
For 6-block confirmation (~60 min)
Mempool Fee Distribution
Current distribution of transactions in the mempool by fee rate (sats/vB)
Loading mempool data...
Did You Know?
Bitcoin fees are based on transaction size, not the amount being sent. Sending $10 or $10,000,000 costs the same in fees if the transaction has the same structure.
Using SegWit addresses can reduce your transaction fees by about 30-40% compared to legacy addresses.
Weekends often have lower network congestion, potentially resulting in lower fees for the same confirmation time.
Bitcoin blocks are mined on average every 10 minutes, but this is just an average—individual block times can vary considerably.
Frequently Asked Questions
How are Bitcoin fees calculated?
Bitcoin fees depend on two components:
- The size of the transaction (in bytes)
- The fee per byte you're willing to pay
Transaction size is calculated based on inputs and outputs. The optimal fee per byte changes constantly based on network congestion.
Using our calculator, simply select how quickly you want your transaction confirmed, and we'll recommend the appropriate fee based on current network conditions.
Pro tip: Higher fees mean faster confirmation times, but you may be able to save money during periods of low network congestion.
How is the fee for Legacy Bitcoin Transactions estimated?
We query our Bitcoin node for the estimated price per byte for your selected confirmation window. The transaction size calculation for legacy transactions is:
This means a Bitcoin transaction with 1 input and 1 output has a size of 189 bytes. The calculation assumes compressed public keys.
You can adjust the number of inputs and outputs using the calculator above to get a more accurate fee estimate for your specific transaction.
What are the differences between Segwit and Legacy Bitcoin Transactions?
Segwit (Segregated Witness) was introduced in BIP-141 and provides several advantages over legacy transactions:
Segwit Benefits
- Smaller transaction size
- Lower fees (especially for multi-sig)
- Fixes transaction malleability issues
- Enables Lightning Network compatibility
Legacy Considerations
- Higher compatibility with older wallets
- Simpler structure for some use cases
- No wallet update required
Toggle the Segwit option in our calculator to see how much you can save by using Segwit transactions.
How is the fee for Segwit transactions estimated?
Segwit introduced a new metric called Transaction Weight, which is calculated by applying different multipliers to different parts of a transaction.
For our calculator, we assume P2WPKH (Pay-to-Witness-Public-Key-Hash) Segwit transactions with the following formula:
This provides a more balanced cost between creating and spending outputs compared to legacy transactions.
What are inputs and outputs in a Bitcoin transaction?
Inputs
Inputs are the source addresses from which coins are sent. If you have 1 BTC spread across three addresses with 0.3, 0.3, and 0.4 BTC respectively, and want to send 0.8 BTC, your transaction would need at least three inputs.
Outputs
Outputs are the destination addresses receiving the coins. Most transactions have at least two outputs: one for the recipient and one for your change. For example, if you send 0.8 BTC from a 1 BTC input, one output would be 0.8 BTC to the recipient and another output would be 0.2 BTC back to your own change address.
More inputs and outputs increase the transaction size and therefore the fee. Use our calculator to adjust these values and see how they affect your fee.
What is the Unconfirmed Transaction Count & Mempool Size?
Unconfirmed Transaction Count shows how many transactions are waiting to be included in blocks. This value varies between nodes as there's no single source of truth for the Bitcoin network.
Mempool Size is the total size of all unconfirmed transactions. Since Bitcoin blocks are limited to approximately 1MB, this metric indicates how backlogged the network is and affects your transaction's inclusion probability.
When to pay attention: During periods of high mempool size, you may need to pay higher fees for timely confirmation. During low congestion, you can save on fees with lower fee rates.
What do the different confirmation targets mean?
The confirmation target slider lets you choose how quickly you want your transaction to be confirmed, measured in blocks. Since Bitcoin blocks are mined approximately every 10 minutes, each block represents about 10 minutes of waiting time.
2-3 blocks
~20-30 min
Higher fees
6-12 blocks
~1-2 hours
Medium fees
18-24 blocks
~3-4 hours
Lower fees
36-48 blocks
~6-8 hours
Lowest fees
Bitcoin miners prioritize transactions with higher fees, so paying more means your transaction is likely to be included in a block sooner. The confirmation target helps you balance cost against speed according to your needs.
When to use faster confirmation: For time-sensitive transactions like payment deadlines or when you need quick access to funds at an exchange.
How do I interpret the Mempool Fee Distribution chart?
The Mempool Fee Distribution chart visualizes the current unconfirmed transactions waiting to be included in blocks, grouped by fee rate (measured in satoshis per virtual byte or sat/vB).
Each bar in the chart represents a different fee rate range, with the height indicating the percentage of pending transactions in that range. The blue gradient indicates the fee level, with darker blue typically representing higher fee rates.
Reading the chart:
- Horizontal axis (X): Fee rate ranges in sat/vB
- Vertical axis (Y): Percentage of unconfirmed transactions
- Colored lines: Fee rate recommendations for different confirmation times (Fast, ~30min, ~1hr, Economy)
- Transaction count: Total number of unconfirmed transactions in the mempool
This chart helps you understand current network demand. If many transactions are paying high fees (bars concentrated on the right side), the network is congested and you'll need to pay more for faster confirmation. If most transactions are paying low fees (bars concentrated on the left), you can likely get quick confirmation with a lower fee.
Why should I care about "Time since last block"?
"Time since last block" shows you how long it has been since the most recent Bitcoin block was mined. While blocks are targeted to be found approximately every 10 minutes, the actual time between blocks varies considerably due to the probabilistic nature of mining.
Short time since last block
If it's been only a few minutes since the last block, there's a good chance another block won't be found immediately (though it's possible). This gives you a bit more time to get your transaction into the next block's candidate set.
Long time since last block
If it's been significantly longer than 10 minutes (e.g., 30+ minutes), a new block is statistically more likely to be found soon. This might be a good time to submit a transaction if you're trying to get into the next block.
This metric can help you time your transactions. For example, if a block was just found and you're not in a hurry, you might wait a bit before submitting your transaction to see if network congestion (and thus fees) decreases. Conversely, if it's been a long time since the last block, miners are likely to find a block soon, so it could be a good time to submit your transaction to get it confirmed quickly.
Remember: Block discovery is probabilistic. While the average time is 10 minutes, individual block times can vary from seconds to hours. This metric gives you useful information but cannot predict exactly when the next block will be mined.
How can historical fee trends help me choose the right fee?
The Historical Fee Rates section shows how transaction fees have varied over time, which can help you identify patterns and make more informed decisions about when to send transactions and what fees to pay.
What to look for in the historical data:
- Day-of-week patterns: Fees often decrease on weekends when there are fewer transactions.
- Time-of-day patterns: Some hours of the day consistently have lower fees than others.
- Trend direction: Whether fees are generally increasing, decreasing, or stable recently.
- Volatility: How much fees fluctuate, which indicates how predictable the market is.
When you compare the current fee (shown in the fee gauge) to the historical average, you can determine if current fees are unusually high or low. If current fees are significantly higher than the historical average, and your transaction isn't urgent, you might consider waiting for fees to decrease.
The detailed fee recommendations (Economy, Standard, Priority, Express) are derived from this historical data, providing optimized fee suggestions for different confirmation time preferences.
Pro strategy: If you notice that fees consistently drop on weekends, you might schedule non-urgent transactions for Saturday or Sunday to save on fees. Similarly, if you notice a recent downward trend in fees, it might be worth waiting a bit longer to send your transaction.
How often is the data updated?
- Satoshi/byte rate: Refreshed every minute
- Mempool & Unconfirmed Transactions: Updated every 3 seconds
- Bitcoin price in USD: Refreshed every second