diff --git a/packages/scheduler/src/SchedulerProfiling.js b/packages/scheduler/src/SchedulerProfiling.js
index a7c7afefef0d6..b2e7781101a7b 100644
--- a/packages/scheduler/src/SchedulerProfiling.js
+++ b/packages/scheduler/src/SchedulerProfiling.js
@@ -103,13 +103,16 @@ export function stopLoggingProfilingEvents(): ArrayBuffer | null {
 
 export function markTaskStart(
   task: {id: number, priorityLevel: PriorityLevel},
-  time: number,
+  ms: number,
 ) {
   if (enableProfiling) {
     profilingState[QUEUE_SIZE]++;
 
     if (eventLog !== null) {
-      logEvent([TaskStartEvent, time, task.id, task.priorityLevel]);
+      // performance.now returns a float, representing milliseconds. When the
+      // event is logged, it's coerced to an int. Convert to microseconds to
+      // maintain extra degrees of precision.
+      logEvent([TaskStartEvent, ms * 1000, task.id, task.priorityLevel]);
     }
   }
 }
@@ -119,7 +122,7 @@ export function markTaskCompleted(
     id: number,
     priorityLevel: PriorityLevel,
   },
-  time: number,
+  ms: number,
 ) {
   if (enableProfiling) {
     profilingState[PRIORITY] = NoPriority;
@@ -127,7 +130,7 @@ export function markTaskCompleted(
     profilingState[QUEUE_SIZE]--;
 
     if (eventLog !== null) {
-      logEvent([TaskCompleteEvent, time, task.id]);
+      logEvent([TaskCompleteEvent, ms * 1000, task.id]);
     }
   }
 }
@@ -137,13 +140,13 @@ export function markTaskCanceled(
     id: number,
     priorityLevel: PriorityLevel,
   },
-  time: number,
+  ms: number,
 ) {
   if (enableProfiling) {
     profilingState[QUEUE_SIZE]--;
 
     if (eventLog !== null) {
-      logEvent([TaskCancelEvent, time, task.id]);
+      logEvent([TaskCancelEvent, ms * 1000, task.id]);
     }
   }
 }
@@ -153,7 +156,7 @@ export function markTaskErrored(
     id: number,
     priorityLevel: PriorityLevel,
   },
-  time: number,
+  ms: number,
 ) {
   if (enableProfiling) {
     profilingState[PRIORITY] = NoPriority;
@@ -161,14 +164,14 @@ export function markTaskErrored(
     profilingState[QUEUE_SIZE]--;
 
     if (eventLog !== null) {
-      logEvent([TaskErrorEvent, time, task.id]);
+      logEvent([TaskErrorEvent, ms * 1000, task.id]);
     }
   }
 }
 
 export function markTaskRun(
   task: {id: number, priorityLevel: PriorityLevel},
-  time: number,
+  ms: number,
 ) {
   if (enableProfiling) {
     runIdCounter++;
@@ -178,37 +181,37 @@ export function markTaskRun(
     profilingState[CURRENT_RUN_ID] = runIdCounter;
 
     if (eventLog !== null) {
-      logEvent([TaskRunEvent, time, task.id, runIdCounter]);
+      logEvent([TaskRunEvent, ms * 1000, task.id, runIdCounter]);
     }
   }
 }
 
-export function markTaskYield(task: {id: number}, time: number) {
+export function markTaskYield(task: {id: number}, ms: number) {
   if (enableProfiling) {
     profilingState[PRIORITY] = NoPriority;
     profilingState[CURRENT_TASK_ID] = 0;
     profilingState[CURRENT_RUN_ID] = 0;
 
     if (eventLog !== null) {
-      logEvent([TaskYieldEvent, time, task.id, runIdCounter]);
+      logEvent([TaskYieldEvent, ms * 1000, task.id, runIdCounter]);
     }
   }
 }
 
-export function markSchedulerSuspended(time: number) {
+export function markSchedulerSuspended(ms: number) {
   if (enableProfiling) {
     mainThreadIdCounter++;
 
     if (eventLog !== null) {
-      logEvent([SchedulerSuspendEvent, time, mainThreadIdCounter]);
+      logEvent([SchedulerSuspendEvent, ms * 1000, mainThreadIdCounter]);
     }
   }
 }
 
-export function markSchedulerUnsuspended(time: number) {
+export function markSchedulerUnsuspended(ms: number) {
   if (enableProfiling) {
     if (eventLog !== null) {
-      logEvent([SchedulerResumeEvent, time, mainThreadIdCounter]);
+      logEvent([SchedulerResumeEvent, ms * 1000, mainThreadIdCounter]);
     }
   }
 }
diff --git a/packages/scheduler/src/__tests__/SchedulerProfiling-test.js b/packages/scheduler/src/__tests__/SchedulerProfiling-test.js
index a1b08488cda5d..cf9f9c5ea8cd8 100644
--- a/packages/scheduler/src/__tests__/SchedulerProfiling-test.js
+++ b/packages/scheduler/src/__tests__/SchedulerProfiling-test.js
@@ -213,7 +213,8 @@ describe('Scheduler', () => {
 
     // Now we can render the tasks as a flamegraph.
     const labelColumnWidth = 30;
-    const msPerChar = 50;
+    // Scheduler event times are in microseconds
+    const microsecondsPerChar = 50000;
 
     let result = '';
 
@@ -221,7 +222,7 @@ describe('Scheduler', () => {
     let mainThreadTimelineColumn = '';
     let isMainThreadBusy = true;
     for (const time of mainThreadRuns) {
-      const index = time / msPerChar;
+      const index = time / microsecondsPerChar;
       mainThreadTimelineColumn += (isMainThreadBusy ? '█' : '░').repeat(
         index - mainThreadTimelineColumn.length,
       );
@@ -244,18 +245,18 @@ describe('Scheduler', () => {
       labelColumn += ' '.repeat(labelColumnWidth - labelColumn.length - 1);
 
       // Add empty space up until the start mark
-      let timelineColumn = ' '.repeat(task.start / msPerChar);
+      let timelineColumn = ' '.repeat(task.start / microsecondsPerChar);
 
       let isRunning = false;
       for (const time of task.runs) {
-        const index = time / msPerChar;
+        const index = time / microsecondsPerChar;
         timelineColumn += (isRunning ? '█' : '░').repeat(
           index - timelineColumn.length,
         );
         isRunning = !isRunning;
       }
 
-      const endIndex = task.end / msPerChar;
+      const endIndex = task.end / microsecondsPerChar;
       timelineColumn += (isRunning ? '█' : '░').repeat(
         endIndex - timelineColumn.length,
       );