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21 Inc Launches Bitcoin Transaction Fee Prediction App

21 Inc has launched a free web app that can help bitcoin users determine what level of fee will ensure a transaction is confirmed.

Updated Sep 11, 2021, 12:07 p.m. Published Feb 10, 2016, 2:36 p.m.
Calculating fees

21 Inc, maker of the Bitcoin Computer, has launched a free web app that can help bitcoin users determine what level of fee will ensure a transaction is confirmed in a given amount of time.

The new service, which can be found at bitcoinfees.21.co, provides a real-time guide to the fee levels currently being paid on the bitcoin network, along with the estimated delay in blocks and estimated time until confirmation. Fees are set in satoshis per byte, a reference to the smallest denomination of bitcoin.

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The launch comes amid a time when transaction levels are increasingly hitting all-time highs, and the community at large has been split on the question of expanding the network's ability to accommodate more transactions per block. To send a bitcoin transaction, users generally must include a transaction fee, which rewards the miners that process transactions and secure the bitcoin blockchain.

For obvious reasons, miners generally prioritise higher fees first, so the larger the fee, the more quickly the transaction will be written to the blockchain and confirmed.

It is not always clear what is the optimum fee level to set, though.

21 Inc said:

"[E]xactly how large a fee you need to get rapid transaction confirmation can be hard to predict in advance, because everyone else sending a bitcoin transaction at the same time is effectively competing with you for the speed of inclusion into the blockchain.

To counter this issue, the company created the web interface for bitcoin users who are manually sending transactions, providing users with a fair idea of the optimum fee to set for their transaction.

21 fee predictor
21 fee predictor

21's fee predictions are based on blockchain data for the last three hours, along with the current pool of unconfirmed transactions (mempool).

"From the simulations, it can be seen how fast transactions with different fees are likely to be included in the upcoming blocks. The predicted delay shown here is chosen to represent a 90% confidence interval," the firm said.

21 stressed that including a fee the app suggests does not guarantee that transactions will end up in the next block, and that the app/API provides a recommendation based on recent performance.

Featured image via Shutterstock. Fee app image via 21 Inc.

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