Start with the roaster's own window
Foundry Coffee Roasters says most of its coffee needs at least 7–10 days after roasting to settle, and that its espresso usually tastes best from the start of week three to the end of week five. The roaster presents these as broad observations from its own roasting, not a universal rule. If you buy Foundry coffee, use that advice as a starting point. For another roaster’s beans, check its recommendation for the coffee and brew method you use.
Two other roasters publish different ranges for their own coffees. Hermanos Coffee Roasters says its Colombian coffees are best 7–21 days after roasting, and describes carbon dioxide release as part of the reason a very fresh bag can taste flat. Clever Coffee says in its FAQ that its beans are best 2–8 weeks after the roast date and recommends drinking them within two weeks of opening.
Use these as separate recommendations for the coffees and methods named. Averaging them would give you a number that no roaster recommended.
Roast date and opening date are different clocks
The roast date is printed on the bag. The opening date is the day you break the seal. Resting guidance normally counts from the roast date, so a bag opened on day 12 is already 12 days off roast, not day one.
Opening the bag starts a separate freshness clock. More oxygen and moisture reach the coffee once the seal is broken. Clever Coffee pairs its 2–8 week roast window with a recommendation to drink the coffee within two weeks of opening. That two-week figure is guidance for Clever's own coffee, not a safety deadline for every bag.
Reseal the bag between brews and note both dates somewhere you will see them. If the bag has no roast date, ask the roaster or use the earliest date you can confirm; otherwise you cannot tell how much of the window has passed.
Taste is the final check
A bloom or crema can tell you the coffee is releasing gas, but it does not tell you the ideal rest day for this bag. Taste is the useful check. Brew a cup with your normal recipe; if it tastes flat and you are early in the roaster's window, give it a few more days and try again. If it tastes balanced, keep brewing it.
When you compare days, keep the recipe the same so the rest day is the only thing changing. A second cup on a later day is more useful than a fixed date chosen in advance.
Plan the bag you bought
If the roaster's preferred window is shorter than the time you need to finish the bag, buy a smaller bag or split it with someone. A large bag is a false economy if the last third sits past the window you actually like.
