diff --git a/proto/anki/scheduler.proto b/proto/anki/scheduler.proto
index 6c0315d73..1823184a3 100644
--- a/proto/anki/scheduler.proto
+++ b/proto/anki/scheduler.proto
@@ -47,6 +47,8 @@ service SchedulerService {
   rpc RepositionDefaults(generic.Empty) returns (RepositionDefaultsResponse);
   rpc ComputeFsrsWeights(ComputeFsrsWeightsRequest)
       returns (ComputeFsrsWeightsResponse);
+  rpc ComputeFsrsWeightsFromItems(ComputeFsrsWeightsFromItemsRequest)
+      returns (ComputeFsrsWeightsResponse);
   rpc GetOptimalRetentionParameters(GetOptimalRetentionParametersRequest)
       returns (GetOptimalRetentionParametersResponse);
   rpc ComputeOptimalRetention(ComputeOptimalRetentionRequest)
@@ -339,6 +341,19 @@ message ComputeFsrsWeightsResponse {
   uint32 fsrs_items = 2;
 }
 
+message ComputeFsrsWeightsFromItemsRequest {
+  repeated FsrsItem items = 1;
+}
+
+message FsrsItem {
+  repeated FsrsReview reviews = 1;
+}
+
+message FsrsReview {
+  uint32 rating = 1;
+  uint32 delta_t = 2;
+}
+
 message ComputeOptimalRetentionRequest {
   repeated float weights = 1;
   uint32 deck_size = 2;
diff --git a/pylib/anki/collection.py b/pylib/anki/collection.py
index ee5c0492b..57281e32a 100644
--- a/pylib/anki/collection.py
+++ b/pylib/anki/collection.py
@@ -15,6 +15,7 @@ from anki import (
     import_export_pb2,
     links_pb2,
     notes_pb2,
+    scheduler_pb2,
     search_pb2,
     stats_pb2,
     sync_pb2,
@@ -52,6 +53,8 @@ GetImageOcclusionNoteResponse = image_occlusion_pb2.GetImageOcclusionNoteRespons
 AddonInfo = ankiweb_pb2.AddonInfo
 CheckForUpdateResponse = ankiweb_pb2.CheckForUpdateResponse
 MediaSyncStatus = sync_pb2.MediaSyncStatusResponse
+FsrsItem = scheduler_pb2.FsrsItem
+FsrsReview = scheduler_pb2.FsrsReview
 
 import copy
 import os
@@ -1338,6 +1341,9 @@ class Collection(DeprecatedNamesMixin):
         else:
             return ComputedMemoryState(desired_retention=resp.desired_retention)
 
+    def compute_weights_from_items(self, items: Iterable[FsrsItem]) -> Sequence[float]:
+        return self._backend.compute_fsrs_weights_from_items(items).weights
+
     # Timeboxing
     ##########################################################################
     # fixme: there doesn't seem to be a good reason why this code is in main.py
diff --git a/rslib/src/scheduler/fsrs/weights.rs b/rslib/src/scheduler/fsrs/weights.rs
index 7464e40b3..e0bc77014 100644
--- a/rslib/src/scheduler/fsrs/weights.rs
+++ b/rslib/src/scheduler/fsrs/weights.rs
@@ -4,6 +4,7 @@ use std::iter;
 use std::thread;
 use std::time::Duration;
 
+use anki_proto::scheduler::ComputeFsrsWeightsFromItemsRequest;
 use anki_proto::scheduler::ComputeFsrsWeightsResponse;
 use fsrs::FSRSItem;
 use fsrs::FSRSReview;
@@ -53,6 +54,22 @@ impl Collection {
         })
     }
 
+    pub fn compute_weights_from_items(
+        &mut self,
+        req: ComputeFsrsWeightsFromItemsRequest,
+    ) -> Result<ComputeFsrsWeightsResponse> {
+        let fsrs = FSRS::new(None)?;
+        let fsrs_items = req.items.len() as u32;
+        let weights = fsrs.compute_weights(
+            req.items.into_iter().map(fsrs_item_proto_to_fsrs).collect(),
+            None,
+        )?;
+        Ok(ComputeFsrsWeightsResponse {
+            weights,
+            fsrs_items,
+        })
+    }
+
     pub(crate) fn revlog_for_srs(
         &mut self,
         search: impl TryIntoSearch,
@@ -209,6 +226,23 @@ impl RevlogEntry {
     }
 }
 
+fn fsrs_item_proto_to_fsrs(item: anki_proto::scheduler::FsrsItem) -> FSRSItem {
+    FSRSItem {
+        reviews: item
+            .reviews
+            .into_iter()
+            .map(fsrs_review_proto_to_fsrs)
+            .collect(),
+    }
+}
+
+fn fsrs_review_proto_to_fsrs(review: anki_proto::scheduler::FsrsReview) -> FSRSReview {
+    FSRSReview {
+        delta_t: review.delta_t,
+        rating: review.rating,
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/rslib/src/scheduler/service/mod.rs b/rslib/src/scheduler/service/mod.rs
index 23c7155f8..e94a966b4 100644
--- a/rslib/src/scheduler/service/mod.rs
+++ b/rslib/src/scheduler/service/mod.rs
@@ -250,6 +250,13 @@ impl crate::services::SchedulerService for Collection {
         self.compute_weights(&input.search)
     }
 
+    fn compute_fsrs_weights_from_items(
+        &mut self,
+        input: scheduler::ComputeFsrsWeightsFromItemsRequest,
+    ) -> Result<scheduler::ComputeFsrsWeightsResponse> {
+        self.compute_weights_from_items(input)
+    }
+
     fn compute_optimal_retention(
         &mut self,
         input: ComputeOptimalRetentionRequest,