This calculator is arithmetic on a table, not a live mixer. Enter quantities from your own 100 Days at Sea session. It will not click the shop.
Material planner
Sawmill Wood
Estimate Wood for Sawmills using the July 2026 community cost of 10 Wood each. Change the inputs if your craft menu shows a different number. This does not subtract Metal.
Required total = materials per upgrade × number of upgrades. Missing = max(required total − materials already owned, 0).
July 2026 community build guides report 10 Wood and 2 Metal per Sawmill, and 3 wooden planks per use. This form totals only the Wood line. Metal is a second ingredient and is not included. Read both costs in the craft menu before you spend.
Drop probability
Companion Drop Chance
Estimate how many companion-chest opens it takes to see one listed drop at least once. Enter the drop percent from the shop. This is not a simulator of the whole chest.
Chance of at least one success = 1 − (1 − chance per attempt) raised to the number of attempts.
This is the chance of at least one success if every open is an independent roll at the percent you type. It does not model a weighted chest with several companions. The 25% default matches the Frog rate reported for the 40-Pearl Fisherman's Chest in mid-2026 companion tables. Confirm the current rate in the Companion Shop.