Minecraft Prior Work Penalty
Prior work records how many generations of anvil operations an item or book has passed through. The count, not the number of enchantments, controls the extra penalty added to the next operation.
Short answer
Minecraft Java Edition adds an exponentially growing prior-work penalty for both anvil slots. Fresh inputs start at zero; every combined result receives a new prior-work count.
penalty = 2^priorWork − 1Prior-work penalty table
The table is generated from the same domain function used by AnvilPilot. A prior-work count of five already adds 31 penalty levels before the transferred enchantments are considered.
| Prior work | Penalty |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 15 |
| 5 | 31 |
| 6 | 63 |
This penalty contributes to one step's cost. Survival does not limit the total levels across a complete plan; it blocks a single anvil operation when that step reaches 40 levels or more.
How combined items get their next count
The result takes the larger history from the two inputs and advances it by one generation:
Combining two fresh books produces prior work 1. Combining a prior-work 1 item with a prior-work 0 book produces prior work 2. This is why balanced book groups can keep the target's history lower than applying every book directly to it.
Fortune Pickaxe with four fresh books
The inputs are Efficiency V, Fortune III, Unbreaking III, and Mending I on fresh books. The optimized work order costs 23 levels; applying the same books sequentially costs 27 levels.
- Step 1Apply Fortune III to the pickaxe
6 levels · prior work 0 + 0 → 1
- Step 2Combine the Unbreaking III and Mending I books
2 levels · prior work 0 + 0 → 1
- Step 3Apply the combined durability book to the pickaxe
7 levels · prior work 1 + 1 → 2
- Step 4Apply Efficiency V last
8 levels · prior work 2 + 0 → 3
The second step combines books before they touch the pickaxe. That small tree saves four total levels and keeps every individual operation comfortably below the Survival limit.
Least total levels vs Preserve future work
Least total levels
Ranks legal plans by the sum of every displayed anvil cost. Use it when the current build is the main priority.
Preserve future work
Ranks legal plans by the final item's prior work first, then uses total levels and stable tie-breakers. Use it when another future anvil operation matters.
Common mistakes
- Treating prior work as the number of enchantments on the item.
- Adding only the target's penalty and forgetting the right-slot input.
- Assuming the cheapest total always leaves the lowest final prior work.
- Checking total plan levels instead of the highest single-step cost.
Prior work FAQ
Does a grindstone reset prior work?
A grindstone removes most enchantments but does not erase an item's prior-work history. Enter the count the item actually carries.
Does combining two fresh books create prior work?
Yes. Both inputs start at zero, and the result becomes max(0, 0) + 1, so the combined book has prior work 1.
Why combine books before the target?
A balanced book tree can transfer several enchantments while increasing the target through fewer prior-work generations.
Is a high prior-work item always impossible?
No. The enchantment transfer cost and both input penalties determine the step. It becomes blocked in Survival only when a single operation reaches 40 or more.
Verified for Java Edition 26.2 on 2026-08-17.