---
title: "Grindstone Drop Rates (JP server)"
description: "Grindstone drop rates on the JP server: 10-12 45.19% (2,131 samples), 10-12 43.85% (1,024), 9-16 40.53% (1,024); 95 stages in total. Updated 2026-10-23. Crowdsourced Arknights drop data by Penguin Statistics."
lang: en
server: JP
item_id: "30093"
as_of: 2026-10-23T14:49:35Z
time_zone: UTC+9
rows: 50
rows_total: 95
canonical: "https://penguin-stats.io/en/result/jp/item/30093"
api: "https://penguin-stats.io/PenguinStats/api/v2/result/matrix?server=JP&itemFilter=30093&show_closed_zones=true"
license: CC BY-NC 4.0
license_url: https://creativecommons.org/licenses/by-nc/4.0/
attribution: "Data: Penguin Statistics (penguin-stats.io), CC BY-NC 4.0"
---

# Grindstone Drop Rates (JP server)

Server: [CN server](https://penguin-stats.io/en/result/cn/item/30093.md) · [US server](https://penguin-stats.io/en/result/us/item/30093.md) · **JP server** · [KR server](https://penguin-stats.io/en/result/kr/item/30093.md)

Drops of Grindstone by stage on the JP server, by percentage, highest first: 50 of 95 stages

| Stage | ID | Loots | Samples | Percentage | Sanity Required Per Item | Sanity | Time Range |
| --- | --- | ---: | ---: | ---: | ---: | ---: | --- |
| [MT-9](https://penguin-stats.io/en/result/jp/stage/act42side_zone1/act42side_09.md) The Masses' Travels | `act42side_09` | 1157 | 1521 | 76.07% | 27.61 | 21 | 2025-10-14 to 2025-11-04 |
| [EP-8](https://penguin-stats.io/en/result/jp/stage/act39side_zone1/act39side_08.md) Exodus From The Pale Sea | `act39side_08` | 1241 | 1788 | 69.41% | 30.26 | 21 | 2025-06-05 to 2025-06-19 |
| [AS-8](https://penguin-stats.io/en/result/jp/stage/act35side_zone1/act35side_08.md) Adventure That Cannot Wait for the Sun | `act35side_08` | 2639 | 3859 | 68.39% | 30.71 | 21 | 2025-01-16 to 2025-02-06 |
| [LE-6](https://penguin-stats.io/en/result/jp/stage/act18sre_zone1/act18side_06_rep.md) Lingering Echoes - Rerun | `act18side_06_rep` | 22830 | 33786 | 67.57% | 31.08 | 21 | 2024-01-05 to 2024-01-15 |
| [LE-6](https://penguin-stats.io/en/result/jp/stage/act18side_zone1/act18side_06.md) Lingering Echoes | `act18side_06` | 888 | 1318 | 67.38% | 31.17 | 21 | 2022-12-27 to 2023-01-10 |
| [CV-7](https://penguin-stats.io/en/result/jp/stage/act28side_zone1/act28side_07.md) Come Catastrophes or Wakes of Vultures | `act28side_07` | 13197 | 19623 | 67.25% | 31.23 | 21 | 2024-03-19 to 2024-04-02 |
| [TW-8](https://penguin-stats.io/en/result/jp/stage/act5sre_zone1/act11d0_08_rep.md) Twilight of Wolumonde - Rerun | `act11d0_08_rep` | 422 | 705 | 59.86% | 30.07 | 18 | 2021-12-17 to 2021-12-27 |
| [TW-8](https://penguin-stats.io/en/result/jp/stage/act11d0_zone1/act11d0_08.md) Twilight of Wolumonde | `act11d0_08` | 2499 | 4253 | 58.76% | 30.63 | 18 | 2020-10-28 to 2020-11-11 |
| [OD-8](https://penguin-stats.io/en/result/jp/stage/act17d0_zone1/act17d0_08.md) Operation Originium Dust | `act17d0_08` | 4472 | 7622 | 58.67% | 30.68 | 18 | 2021-08-18 to 2021-09-01 |
| [OD-8](https://penguin-stats.io/en/result/jp/stage/act1r6sre_zone1/act17d0_08_rep.md) Operation Originium Dust - Rerun | `act17d0_08_rep` | 681 | 1165 | 58.45% | 30.79 | 18 | 2024-09-19 to 2024-09-29 |
| [BI-8](https://penguin-stats.io/en/result/jp/stage/act14side_zone1/act14side_08.md) Break The Ice | `act14side_08` | 2302 | 4004 | 57.49% | 31.31 | 18 | 2022-06-30 to 2022-07-14 |
| [BI-8](https://penguin-stats.io/en/result/jp/stage/act14sre_zone1/act14side_08_rep.md) Break The Ice - Rerun | `act14side_08_rep` | 6000 | 10464 | 57.34% | 31.39 | 18 | 2023-06-13 to 2023-06-23 |
| [13-21](https://penguin-stats.io/en/result/jp/stage/main_13/main_13-19.md) Episode 13 (Standard) | `main_13-19` | 15 | 30 | 50.00% | 48.00 | 24 | 2024-03-19 until now |
| [GT-6](https://penguin-stats.io/en/result/jp/stage/act13d2_zone1/a001_06_rep.md) The Knight & The Hunters - Rerun | `a001_06_rep` | 787 | 1641 | 47.96% | 31.28 | 15 | 2020-11-26 to 2020-12-06 |
| [DC-8](https://penguin-stats.io/en/result/jp/stage/act14mini_zone1/act14mini_08.md) Chunfen | `act14mini_08` | 54 | 115 | 46.96% | 44.72 | 21 | 2023-08-22 to 2023-08-29 |
| [10-12](https://penguin-stats.io/en/result/jp/stage/main_10/main_10-11.md) Episode 10 (Standard) | `main_10-11` | 963 | 2131 | 45.19% | 46.47 | 21 | 2022-10-19 until now |
| [10-12](https://penguin-stats.io/en/result/jp/stage/main_10_tough/tough_10-11.md) Episode 10 (Tough) | `tough_10-11` | 449 | 1024 | 43.85% | 47.89 | 21 | 2022-10-19 until now |
| [9-16](https://penguin-stats.io/en/result/jp/stage/main_9/main_09-14.md) Episode 9 | `main_09-14` | 415 | 1024 | 40.53% | 44.41 | 18 | 2022-03-17 until now |
| [AF-8](https://penguin-stats.io/en/result/jp/stage/act6d5_zone1/act6d5_08.md) Ancient Forge | `act6d5_08` | 766 | 1905 | 40.21% | 44.76 | 18 | 2020-07-29 to 2020-08-12 |
| [12-8](https://penguin-stats.io/en/result/jp/stage/main_12/main_12-07.md) Episode 12 (Standard) | `main_12-07` | 69 | 192 | 35.94% | 58.43 | 21 | 2023-10-24 until now |
| [5-7](https://penguin-stats.io/en/result/jp/stage/main_5/main_05-07.md) Episode 5 | `main_05-07` | 921 | 2598 | 35.45% | 59.24 | 21 | 2020-02-26 until now |
| [4-8](https://penguin-stats.io/en/result/jp/stage/main_4/main_04-08.md) Episode 4 | `main_04-08` | 2288 | 6514 | 35.12% | 59.79 | 21 | 2020-01-16 until now |
| [14-5](https://penguin-stats.io/en/result/jp/stage/main_14/main_14-04.md) Episode 14 (Standard) | `main_14-04` | 23 | 67 | 34.33% | 61.17 | 21 | 2024-11-14 until now |
| [13-21](https://penguin-stats.io/en/result/jp/stage/main_13_tough/tough_13-19.md) Episode 13 (Tough) | `tough_13-19` | 1 | 3 | 33.33% | 72.00 | 24 | 2024-03-19 until now |
| [3-3](https://penguin-stats.io/en/result/jp/stage/main_3/main_03-03.md) Episode 3 | `main_03-03` | 2552 | 7872 | 32.42% | 46.27 | 15 | 2020-01-16 until now |
| [7-17](https://penguin-stats.io/en/result/jp/stage/main_7/main_07-15.md) Episode 7 | `main_07-15` | 593 | 1838 | 32.26% | 65.09 | 21 | 2020-12-30 until now |
| [GT-6](https://penguin-stats.io/en/result/jp/stage/permanent_sidestory_1_zone1/a001_06_perm.md) The Knight & The Hunters - Side Story | `a001_06_perm` | 201 | 648 | 31.02% | 48.36 | 15 | 2021-09-30 until now |
| [12-8](https://penguin-stats.io/en/result/jp/stage/main_12_tough/tough_12-07.md) Episode 12 (Tough) | `tough_12-07` | 127 | 432 | 29.40% | 71.43 | 21 | 2023-10-24 until now |
| [TW-8](https://penguin-stats.io/en/result/jp/stage/permanent_sidestory_4_zone1/act11d0_08_perm.md) Twilight of Wolumonde - Side Story | `act11d0_08_perm` | 48 | 180 | 26.67% | 67.50 | 18 | 2021-12-31 until now |
| [14-5](https://penguin-stats.io/en/result/jp/stage/main_14_tough/tough_14-04.md) Episode 14 (Tough) | `tough_14-04` | 9 | 37 | 24.32% | 86.33 | 21 | 2024-11-14 until now |
| [BI-8](https://penguin-stats.io/en/result/jp/stage/permanent_sidestory_11_zone1/act14side_08_perm.md) Break The Ice - Side Story | `act14side_08_perm` | 14 | 59 | 23.73% | 75.86 | 18 | 2023-06-27 until now |
| [6-14](https://penguin-stats.io/en/result/jp/stage/main_6/main_06-12.md) Episode 6 | `main_06-12` | 34 | 148 | 22.97% | 78.35 | 18 | 2020-06-30 until now |
| [Operation Pyrite Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_1.md) Supplies | `randomMaterialRune_1` | 24 | 264 | 9.09% | — | — | 2020-11-25 until now |
| [Operation Blade Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_2.md) Supplies | `randomMaterialRune_2` | 26 | 300 | 8.67% | — | — | 2021-02-18 until now |
| [Operation Dawnseeker Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_8.md) Supplies | `randomMaterialRune_8` | 5 | 62 | 8.06% | — | — | 2022-09-13 until now |
| [Operation Lead Seal Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_4.md) Supplies | `randomMaterialRune_4` | 4 | 58 | 6.90% | — | — | 2021-07-27 until now |
| [Operation Pine Soot Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_7.md) Supplies | `randomMaterialRune_7` | 5 | 84 | 5.95% | — | — | 2022-06-23 until now |
| [Operation Barrenland Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_0.md) Supplies | `randomMaterialRune_0` | 18 | 322 | 5.59% | — | — | 2020-09-24 until now |
| [Operation Spectrum Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_5.md) Supplies | `randomMaterialRune_5` | 3 | 56 | 5.36% | — | — | 2021-11-25 until now |
| [MN-8](https://penguin-stats.io/en/result/jp/stage/permanent_sidestory_6_zone1/act13d5_08_perm.md) Maria Nearl - Side Story | `act13d5_08_perm` | 3 | 66 | 4.54% | 396.04 | 18 | 2022-04-14 until now |
| [15-5](https://penguin-stats.io/en/result/jp/stage/main_15/main_15-04.md) Episode 15 | `main_15-04` | 1 | 23 | 4.35% | 482.98 | 21 | 2025-09-30 until now |
| [11-5](https://penguin-stats.io/en/result/jp/stage/main_11/main_11-04.md) Episode 11 (Standard) | `main_11-04` | 4 | 101 | 3.96% | 530.30 | 21 | 2023-04-27 until now |
| [Operation Wild Scales Supplies](https://penguin-stats.io/en/result/jp/stage/gachabox/randomMaterialRune_6.md) Supplies | `randomMaterialRune_6` | 3 | 83 | 3.61% | — | — | 2022-03-15 until now |
| [12-13](https://penguin-stats.io/en/result/jp/stage/main_12_tough/tough_12-11.md) Episode 12 (Tough) | `tough_12-11` | 16 | 469 | 3.41% | 703.40 | 24 | 2023-10-24 until now |
| [WD-7](https://penguin-stats.io/en/result/jp/stage/permanent_sub_2_zone1/act18d0_07_perm.md) A Walk in The Dust - Intermezzi | `act18d0_07_perm` | 2 | 67 | 2.99% | 603.02 | 18 | 2021-10-21 until now |
| [7-9](https://penguin-stats.io/en/result/jp/stage/main_7/main_07-07.md) Episode 7 | `main_07-07` | 35 | 1241 | 2.82% | 744.68 | 21 | 2020-12-30 until now |
| [11-11](https://penguin-stats.io/en/result/jp/stage/main_11/main_11-09.md) Episode 11 (Standard) | `main_11-09` | 3 | 116 | 2.59% | 812.06 | 21 | 2023-04-27 until now |
| [10-9](https://penguin-stats.io/en/result/jp/stage/main_10/main_10-08.md) Episode 10 (Standard) | `main_10-08` | 1 | 41 | 2.44% | 861.01 | 21 | 2022-10-19 until now |
| [11-12](https://penguin-stats.io/en/result/jp/stage/main_11/main_11-10.md) Episode 11 (Standard) | `main_11-10` | 32 | 1360 | 2.35% | 1019.97 | 24 | 2023-04-27 until now |
| [11-5](https://penguin-stats.io/en/result/jp/stage/main_11_tough/tough_11-04.md) Episode 11 (Tough) | `tough_11-04` | 8 | 350 | 2.29% | 918.64 | 21 | 2023-04-27 until now |

Samples: runs of the stage reported in the time range. Loots: total number of the item dropped in those runs. Percentage = Loots ÷ Samples, the expected number dropped per run, which can exceed 100%. Sanity Required Per Item = Sanity ÷ Percentage. Time Range: since the drop table of the stage last changed.

Updated 2026-10-23 23:49 (UTC+9). [Full data (JSON)](https://penguin-stats.io/PenguinStats/api/v2/result/matrix?server=JP&itemFilter=30093&show_closed_zones=true). License: [CC BY-NC 4.0](https://creativecommons.org/licenses/by-nc/4.0/)

## Related Items

- [Grindstone Pentahydrate](https://penguin-stats.io/en/result/jp/item/30094.md) `30094`