Updated
What the preview shows before you save
The preview answers one question before you save: how many times this alert would have fired over recent stored prices. It does not send messages, and it does not change the alert until you save. The marks are a replay of prices the product already stored. They are not a statement about the next price.
This page says what the replay checks, what a short history looks like, and what the chart is. It does not tell you to buy, sell, or hold.
What the replay checks
The window is the last 30 days, ending at the start of the current minute in UTC. Every whole minute in between is one check, at the end of that minute, on final 1-minute candles. The price is that minute's close. The alert is treated as set at the start of those 30 days, armed, and not already in a wait. A missing candle is a gap, not a zero. Asking for the preview saves nothing.
An alert on one coin replays that coin. An alert on your watchlist replays the coins your plan includes, in list order, skipping a coin that is no longer listed, and at most 10 coins. If the list is longer, the screen says it used the first of that total. The coins are added together. A watchlist replay does not draw a chart.
Live checks follow the plan. On Free they run about every 5 minutes. Trader and Pro, at launch, run about every minute. The preview checks every stored minute, so it can show a fire that a 5-minute check would miss. On Free, a 15-minute window says that on the screen.
The count is the fires over those 30 days. A second line says how many of them were in the last 7 days. That 7-day line is omitted when the count is zero.
When the history is short
A check counts as answered when the replay could decide: it fired, the condition was not met, the wait was still running, the alert was waiting to arm again, or it armed again. Days checked is answered checks divided by 1440, to one decimal.
A coin with under 7 days of answered checks is unavailable. It has no count and no chart. If every coin is unavailable, the screen says there is not enough price history to preview this yet, and that you can still save. An empty preview is not a count of zero.
If the preview can answer, but days checked are under 28.5, it is partial. 28.5 is 95 percent of 30. The screen says how many of the last 30 days it could check. The count stays, with that line under it.
Volume spikes, and unusual moves on a 4-hour or 24-hour window, need candles from before those 30 days. The feed keeps 35 days, so the oldest checks may have no answer. That is why those previews often name the days they could check.
If the preview does not finish, the screen says so, and you can still save. That line covers a busy preview and a failed request. Closing the page cancels the one in flight.
The count, the chart, and the label
A noise check sits beside the count. The word comes from fires per day checked, times 30, rounded. Quiet is 8 or fewer. Busy is 9 to 30. Noisy is more than 30. Those bands are this replay, not the daily message limit. The line also names your limit. The default is 8, and you can set 1 to 30. When the fire count itself is over 30, the screen says that is more than once a day, on average.
A percent move, a volume spike, or an unusual move can offer a quieter setting and a more-often setting. A percent tries the amount times 1.5 and times 0.7. A volume spike tries the next step among 1.5, 2, 3, 5, 10, and 20. An unusual move tries a longer wait and a shorter wait. A side appears only when the count really changes. Price levels do not get these.
On a one-coin alert, the chart is 360 points, 2 hours apart. Each point is the close of a real minute in that bucket, or the minute of a fire in it, so the mark sits on the line. A bucket with no candle is empty. The chart is omitted when the preview is unavailable, and it is omitted for a watchlist. Empty points are not filled in. The chart's name says it is the last 30 days and how many marks there are.
The fire list is newest first, at most 300 lines. The count above it is the full total. Each line has the check time, that minute's close, and the event sentence an alert would use.
What the preview does not show
It does not show the price after a fire. A receipt is that later price, and the preview stops at the fire. Quiet, Busy, and Noisy are counts, not a rating. Every number comes from stored candles. A short history stays blank. It does not invent a count.
The label on the preview is "Backtest · last 30 days · hypothetical · not a forecast".
Terminal shows that count, the chart, and the label before you save, and it treats the preview as a replay of stored prices rather than a recommendation.
FAQ
Can I save when the preview has no count?
Yes. Under 7 days of answered checks, the count and the chart stay empty, and saving stays allowed. The screen says there is not enough price history yet. That empty state is not a count of zero.
Why can the preview show a fire the live check missed?
On Free, live checks run about every 5 minutes. The preview checks every stored minute. A move between live checks can appear in the 30-day replay. A 15-minute window on Free says so beside the alert.
Does the preview show the price after a fire?
No. It stops at the minute the alert would have fired, and at that minute's close. The price 1 hour, 4 hours, 24 hours, or 7 days later is a receipt, on another screen. The preview does not compute it.
Sources. The figures on this page are the product's preview rules and the words on the builder. They are not a live price.