By the end, you’ll be able to…
- Distinguish unconfirmed and confirmed transactions.
- Explain why confirmation policies differ.
Three questions to carry into this lesson.
Blocks are not appointments
An unconfirmed transaction has not yet been included in the accepted chain of the observing node. Inclusion gives it a confirmation; later blocks build additional work above that history. The target interval between Bitcoin blocks is an average, not a timetable. A payment does not become faulty just because a stopwatch passes ten minutes.
Why recipients wait
Competing chain histories and double-spend attempts make a first observation different from a stronger settlement assessment. A recipient chooses a policy appropriate to the value, delivery reversibility and threat they face. There is no universal count that makes every transaction absolutely irreversible. A café, a digital download and a large irreversible delivery can reasonably need different procedures.
Communicate the condition
Suppose a fictional artist’s checkout says “awaiting confirmation.” The useful message tells the buyer that the payment has been seen and what remains before delivery. It should not imply that a second payment is needed. If an explorer and wallet disagree, inspect their network, transaction identifier and synchronization state. Avoid escalating from uncertainty to a rushed resend; first establish which transaction each screen is describing.
Practice on paper
A transaction is included in block 100. The observer’s current tip is block 102 on the same chain. How many confirmations does the transaction have in this example?
I’ve tried it — show the worked answer
Three: inclusion at 100 counts as one, followed by 101 and 102. This arithmetic does not decide an appropriate acceptance policy or guarantee that no reorganization can occur.
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One idea to take with you
Waiting for evidence is different from assuming something is broken.
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