diff --git a/mcp/server_http.py b/mcp/server_http.py
index abbc7a9..96f7d1b 100644
--- a/mcp/server_http.py
+++ b/mcp/server_http.py
@@ -1878,6 +1878,9 @@ def get_plan_for_day(date: str | None = None) -> dict[str, Any]:
         # Lane on (set via set_held_ll). Those rides' predicted waits are
         # LL returns, not standby — don't treat their standby as a signal.
         "held_lls": chosen.get("ll_holds", {}),
+        # {ride_id: actual wait min} captured from the phone on Mark done —
+        # calibration signal (predicted vs actual) for done-via-web rides.
+        "actual_waits": chosen.get("actual_waits", {}),
         "completed_rides": chosen.get("completed_rides", []),
         "dropped_rides": chosen.get("dropped_rides", []),
         "show_selections": chosen.get("show_selections", []),
diff --git a/web/src/app/replan/ReplanControls.tsx b/web/src/app/replan/ReplanControls.tsx
index 2bd73f0..335793d 100644
--- a/web/src/app/replan/ReplanControls.tsx
+++ b/web/src/app/replan/ReplanControls.tsx
@@ -9,7 +9,13 @@
 
 import { useState, useTransition } from "react";
 
-import { applyDone, applyDrop, applyNextUp, type ReplanResult } from "./actions";
+import {
+  applyActualWait,
+  applyDone,
+  applyDrop,
+  applyNextUp,
+  type ReplanResult,
+} from "./actions";
 
 export default function ReplanControls({
   planId,
@@ -18,6 +24,7 @@ export default function ReplanControls({
   initiallyDropped,
   initiallyNext,
   initiallyDone,
+  initialActual,
   emphasize,
 }: {
   planId: string;
@@ -26,6 +33,7 @@ export default function ReplanControls({
   initiallyDropped: boolean;
   initiallyNext: boolean;
   initiallyDone: boolean;
+  initialActual: number | null;
   /** Which action to lead with for this ride. */
   emphasize: "drop" | "next";
 }) {
@@ -69,6 +77,11 @@ export default function ReplanControls({
         <span className="rounded-full bg-ok/15 px-3 py-1 text-xs font-medium text-ok">
           Done ✓
         </span>
+        <ActualWait
+          planId={planId}
+          rideId={rideId}
+          initial={initialActual}
+        />
         <TextBtn onClick={unDone} disabled={pending} label="Undo" />
         <Err error={error} />
       </Row>
@@ -157,6 +170,50 @@ export default function ReplanControls({
   );
 }
 
+/** Optional "actual wait" capture on a done ride — calibration data.
+ *  Blank is fine; saves on blur. */
+function ActualWait({
+  planId,
+  rideId,
+  initial,
+}: {
+  planId: string;
+  rideId: string;
+  initial: number | null;
+}) {
+  const [pending, start] = useTransition();
+  const [saved, setSaved] = useState(initial !== null);
+  const [err, setErr] = useState<string | null>(null);
+
+  const save = (v: string) => {
+    setErr(null);
+    start(async () => {
+      const res = await applyActualWait(planId, rideId, v);
+      if (res.ok) setSaved(v.trim() !== "");
+      else setErr(res.error ?? "");
+    });
+  };
+  return (
+    <span className="inline-flex items-center gap-1 text-xs text-fg-3">
+      actual
+      <input
+        type="number"
+        min={0}
+        max={600}
+        inputMode="numeric"
+        defaultValue={initial ?? ""}
+        placeholder="—"
+        disabled={pending}
+        onBlur={(e) => save(e.target.value)}
+        className="w-12 rounded border border-line bg-bg-0 px-1 py-0.5 text-center text-fg-0"
+      />
+      min
+      {saved && <span className="text-ok">✓</span>}
+      {err && <span className="text-warn">{err}</span>}
+    </span>
+  );
+}
+
 function Row({ children }: { children: React.ReactNode }) {
   return <div className="flex flex-wrap items-center gap-2">{children}</div>;
 }
diff --git a/web/src/app/replan/actions.ts b/web/src/app/replan/actions.ts
index 816056f..f76b006 100644
--- a/web/src/app/replan/actions.ts
+++ b/web/src/app/replan/actions.ts
@@ -19,6 +19,7 @@ import {
   setHeldLl,
   setPlanNextUp,
   setPlanOrder,
+  setRideActualWait,
   setRideDone,
   setRideDropped,
 } from "@/lib/dynamodb-writes";
@@ -218,6 +219,35 @@ export async function applyHeldLl(
   return { ok: true };
 }
 
+/**
+ * Record an OPTIONAL actual wait (minutes) for a ride, or clear it
+ * (empty). Never required — Mark done works without it; this just
+ * captures calibration data (predicted vs actual) when the user offers it.
+ */
+export async function applyActualWait(
+  planId: string,
+  rideId: string,
+  minutes: string,
+): Promise<ReplanResult> {
+  const bad = await gate(planId, rideId);
+  if (bad) return bad;
+  let val: number | null = null;
+  if (minutes.trim() !== "") {
+    const n = Number(minutes);
+    if (!Number.isFinite(n) || n < 0 || n > 600) {
+      return { ok: false, error: "Enter minutes (0–600)." };
+    }
+    val = Math.round(n);
+  }
+  try {
+    await setRideActualWait(planId, rideId, val);
+  } catch {
+    return { ok: false, error: "Couldn't save — try again." };
+  }
+  revalidatePath("/replan");
+  return { ok: true };
+}
+
 /** Mark a ride done (done=true) or un-done (false) from /replan. */
 export async function applyDone(
   planId: string,
diff --git a/web/src/app/replan/page.tsx b/web/src/app/replan/page.tsx
index 694996b..9d1d62f 100644
--- a/web/src/app/replan/page.tsx
+++ b/web/src/app/replan/page.tsx
@@ -132,6 +132,7 @@ export default async function ReplanPage({
                   initiallyDropped={droppedSet.has(r.ride_id)}
                   initiallyNext={isNext}
                   initiallyDone={doneSet.has(r.ride_id)}
+                  initialActual={ctx.actual_waits[r.ride_id] ?? null}
                   emphasize={isAffected ? affectedEmphasis : "drop"}
                 />
               </div>
diff --git a/web/src/lib/dynamodb-writes.test.ts b/web/src/lib/dynamodb-writes.test.ts
index 96ebca6..6f63b1f 100644
--- a/web/src/lib/dynamodb-writes.test.ts
+++ b/web/src/lib/dynamodb-writes.test.ts
@@ -238,3 +238,24 @@ describe("setHeldLl", () => {
     expect(sendMock.mock.calls[0][0].input.UpdateExpression).toBe("REMOVE ll_holds.#r");
   });
 });
+
+describe("setRideActualWait", () => {
+  it("ensures the map then sets the ride's actual minutes", async () => {
+    sendMock.mockResolvedValue({});
+    const { setRideActualWait } = await import("./dynamodb-writes");
+    await setRideActualWait("p1", "tron", 45);
+    expect(sendMock).toHaveBeenCalledTimes(2);
+    const set = sendMock.mock.calls[1][0].input;
+    expect(set.UpdateExpression).toBe("SET actual_waits.#r = :m");
+    expect(set.ExpressionAttributeNames["#r"]).toBe("tron");
+    expect(set.ExpressionAttributeValues[":m"]).toBe(45);
+  });
+
+  it("REMOVEs when cleared (null)", async () => {
+    sendMock.mockResolvedValue({});
+    const { setRideActualWait } = await import("./dynamodb-writes");
+    await setRideActualWait("p1", "tron", null);
+    expect(sendMock).toHaveBeenCalledOnce();
+    expect(sendMock.mock.calls[0][0].input.UpdateExpression).toBe("REMOVE actual_waits.#r");
+  });
+});
diff --git a/web/src/lib/dynamodb-writes.ts b/web/src/lib/dynamodb-writes.ts
index 9cd554e..9ac1a71 100644
--- a/web/src/lib/dynamodb-writes.ts
+++ b/web/src/lib/dynamodb-writes.ts
@@ -399,6 +399,49 @@ export async function setHeldLl(
   }
 }
 
+/**
+ * Record (minutes) or clear (null) the ACTUAL wait for a ride, in the
+ * actual_waits map — the calibration signal (predicted vs actual). Atomic
+ * per-key map update, ll_holds-style; ensured first so the nested SET
+ * can't fail on a missing map. Paired with Mark done on the schedule.
+ */
+export async function setRideActualWait(
+  planId: string,
+  rideId: string,
+  minutes: number | null,
+): Promise<void> {
+  const Key = { PK: `USER#${SHARED_TRIP_USER}`, SK: `PLAN#${planId}` };
+  if (minutes !== null) {
+    await client.send(
+      new UpdateCommand({
+        TableName: tableName,
+        Key,
+        UpdateExpression: "SET actual_waits = if_not_exists(actual_waits, :empty)",
+        ExpressionAttributeValues: { ":empty": {} },
+        ConditionExpression: "attribute_exists(PK)",
+      }),
+    );
+    await client.send(
+      new UpdateCommand({
+        TableName: tableName,
+        Key,
+        UpdateExpression: "SET actual_waits.#r = :m",
+        ExpressionAttributeNames: { "#r": rideId },
+        ExpressionAttributeValues: { ":m": minutes },
+      }),
+    );
+  } else {
+    await client.send(
+      new UpdateCommand({
+        TableName: tableName,
+        Key,
+        UpdateExpression: "REMOVE actual_waits.#r",
+        ExpressionAttributeNames: { "#r": rideId },
+      }),
+    );
+  }
+}
+
 // ─── "Ask Claude" daily rate limit (2026-07-03) ──────────────────────
 //
 // The /replan "Ask Claude" server action costs real Anthropic tokens, so
diff --git a/web/src/lib/dynamodb.ts b/web/src/lib/dynamodb.ts
index 2bd7670..5d807a0 100644
--- a/web/src/lib/dynamodb.ts
+++ b/web/src/lib/dynamodb.ts
@@ -349,6 +349,8 @@ export interface ReplanContext {
   held_lls: Record<string, string>;
   /** ride_ids marked done from /replan. */
   completed_ride_ids: string[];
+  /** {ride_id: actual wait minutes} captured on Mark done (optional). */
+  actual_waits: Record<string, number>;
 }
 
 /**
@@ -370,6 +372,7 @@ export async function getReplanContext(
     | (Omit<PlanRow, "ride_sequence"> & {
         dropped_ride_ids?: Set<string> | string[];
         completed_ride_ids?: Set<string> | string[];
+        actual_waits?: Record<string, number>;
         next_up?: string;
         ll_holds?: Record<string, string>;
         plan_order?: string[];
@@ -412,5 +415,6 @@ export async function getReplanContext(
     next_up: r.next_up ?? null,
     held_lls: r.ll_holds ?? {},
     completed_ride_ids: [...(r.completed_ride_ids ?? [])],
+    actual_waits: r.actual_waits ?? {},
   };
 }