Understanding Bitcoin Fees and Moon Wallet: Why Your Balance Fluctuated

As users of cryptocurrency services like Bitcoin, blockchain platforms, or wallets, it’s not uncommon to encounter issues with balances and fees. In this article, we’ll delve into the concept of bitcoin fees, specifically how they work in the context of Moon Wallet, as well as why you experienced a significant fluctuation in your balance.

Bitcoin Fees: A Brief Overview

Bitcoin (BTC) fees are charges associated with transactions on the Bitcoin network. They’re calculated based on the number of confirmations required for a transaction to be included in a block, as well as the average time it takes to confirm a transaction across the entire network. These fees can vary greatly depending on the complexity of the transaction and the network’s load.

Moon Wallet Fees: A Detailed Analysis

When you use Muun Wallet to send or receive Bitcoin, you’re essentially initiating a transaction with your wallet account. The fee rate is determined by Muun’s algorithm, which takes into account various factors such as:

• Transaction amount: The larger the transaction amount, the higher the fee.

• Network congestion: When the network is congested, fees are increased to discourage spam transactions and ensure a faster transaction time.

• Confirmations: The more confirmations required for a transaction (e.g., 6 confirmations), the higher the fee.

In your scenario, you send 10,000 Sats to an external BTC wallet using Muun’s fee rate of 1 sat per vB (total value of Bitcoin). This means that for every 0.01 Sats in value, you paid a 1 sat charge.

Why Your Balance Fluctuated

You initially had 10,500 Sats in your Moon Wallet. When you sent the 10,000 Sats to the external BTC wallet, you expected your balance to remain at 10,500 Sats after the transaction. However, due to various factors that we’ll explore below, your actual balance decreased.

Here are a few possible reasons why:

• Transaction complexity

  : The external Bitcoin wallet might have required more confirmations (e.g., multiple rewrites) than expected, increasing the overall fee.

• Network congestion: As mentioned earlier, network congestion can lead to higher fees and slower transaction times.

• Rate limits or constraints: Moon may have imposed rate limits on your transactions, restricting the number of transactions you can make within a certain timeframe.

The Bitcoin Fee Calculation

To estimate the fee, we’ll need to calculate the number of confirmations required for the transaction:

Assuming an average block time of 10 minutes and a maximum of 6 confirmations per transaction:

Transaction amount: 10,000 Sats (approx. 1 BTC)

Network congestion factor: 2 (a rough estimate for moderate network load)


Total transactions: 10,500 / 0.5 = 21,000 transactions

Maximum confirmations: 6



Estimated number of blocks involved in the transaction

Estimated blocks: 21,000 / 100 (avg. block time) ≈ 210 blocks


Block time: 10 minutes

Transaction time: 1 minute (avg.)



Estimated confirmations required for the transaction

Confirmations: 210 * 6 = 1260 confirmations


Total fee calculation:


Fee per vB = Total value of Bitcoin / Number of confirmations × 1 sat/vB

= BTC amount × 1 sat/vB / Confirmations × 1 sat/vB

= 10,000 Sats / 1260 confirmations ≈ 7.91 sat



Calculating the fee in Muun's currency (sat)

Fee = Fee per vB × Number of SATs

= 7.91 sat × 10000 SATs ≈ 79,100 sat

Why the Fluctuation?

The decrease in your balance from 10,500 Sats to approximately 280 Sats is likely due to a combination of factors:

• External transaction complexity: The external Bitcoin wallet might have required more confirmations than expected.

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