OSRS High Alch Calculator

High Level Alchemy is a level 55 Magic spell that converts an item into coins equal to its high alch value. Each cast takes 1 nature rune and 5 fire runes — the fire runes are free if you wield a fire staff, which is why every serious alcher uses one — and gives 65 Magic XP. At the maximum rate of roughly 1,200 casts per hour that is about 78,000 Magic XP per hour, castable while you do almost anything else.

The profit on a cast is simple: high alch value − item buy price − nature rune price. The alch value is fixed by the game; the other two numbers move with the Grand Exchange all day. That is why a static list of "best alch items" goes stale within hours — this table re-ranks every alchable item with the live GE feed instead.

Items are priced at their buy price — the same number the item's own page shows as Buy Price, so an alch row and an item page never disagree about what buying costs. That is the price a buy offer fills at rather than a mid price, and it assumes the offer fills; on thin items it may not. Buying incurs no GE tax (the 2% tax is charged to sellers), so there is no tax anywhere in the formula.

Alching is a bulk activity — nobody buys one yew longbow — so the table ranks by max profit: profit per cast times the item's 4-hour GE buy limit, the most one buy window can be worth. A 60 GP margin on an 18,000-limit item beats a 400 GP margin on a limit of 70.

Daily volume is the reality check on both numbers: it is how many actually trade per day, and an item that "profits" 500 GP but trades twenty times a day usually has a stale price you will never get filled at — let alone thousands of times. The minimum-volume filter hides that junk by default; raise it if you plan to alch serious quantities.