diff --git a/src/main/java/com/mr/domain/history/dto/res/HistoryDetailResponseDTO.java b/src/main/java/com/mr/domain/history/dto/res/HistoryDetailResponseDTO.java
index c346346d..576ca7bb 100644
--- a/src/main/java/com/mr/domain/history/dto/res/HistoryDetailResponseDTO.java
+++ b/src/main/java/com/mr/domain/history/dto/res/HistoryDetailResponseDTO.java
@@ -3,6 +3,7 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.mr.domain.analysis.entity.Analysis;
 import com.mr.domain.analysis.entity.enums.AnalysisStatus;
+import com.mr.domain.analysis.service.AnalysisBarCalculator.BarMetrics;
 import com.mr.domain.backingtrack.entity.BackingTrack;
 import com.mr.domain.playing.entity.MidiEventData;
 import com.mr.domain.playing.entity.Playing;
@@ -29,7 +30,8 @@ public record HistoryDetailResponseDTO(
         List<AnalysisSummary> analyses
 ) {
 
-    public static HistoryDetailResponseDTO from(Playing playing, List<Analysis> analyses, String recordingFileUrl) {
+    public static HistoryDetailResponseDTO from(
+            Playing playing, List<Analysis> analyses, String recordingFileUrl, BarMetrics barMetrics) {
         BackingTrack backingTrack = playing.getBackingTrack();
 
         return new HistoryDetailResponseDTO(
@@ -46,8 +48,8 @@ public static HistoryDetailResponseDTO from(Playing playing, List<Analysis> anal
                 backingTrack != null ? backingTrack.getAudioFileUrl() : null,
                 playing.getMidiData().stream().map(MidiEvent::from).toList(),
                 backingTrack != null ? backingTrack.getMidiData() : null,
-                null, // TODO: totalBars - playtimeSec/bpm 기반 추정 가능, 정확도 논의 후 추가
-                analyses.stream().map(AnalysisSummary::from).toList()
+                barMetrics != null ? barMetrics.totalBars() : null,
+                analyses.stream().map(analysis -> AnalysisSummary.from(analysis, barMetrics)).toList()
         );
     }
 
@@ -85,7 +87,7 @@ public record AnalysisSummary(
             LocalDateTime createdAt
     ) {
 
-        public static AnalysisSummary from(Analysis analysis) {
+        public static AnalysisSummary from(Analysis analysis, BarMetrics barMetrics) {
             return new AnalysisSummary(
                     analysis.getId(),
                     analysis.getStartBar(),
@@ -93,9 +95,19 @@ public static AnalysisSummary from(Analysis analysis) {
                     analysis.getStartBar() + "마디-" + analysis.getEndBar() + "마디 분석 리포트",
                     analysis.getSummary(),
                     analysis.getStatus(),
-                    null, // TODO: estimatedSeconds 소스 없음
+                    toEstimatedSeconds(analysis, barMetrics),
                     analysis.getCreatedAt()
             );
         }
+
+        // 분석 구간(startBar~endBar)의 재생 길이 산정
+        private static Integer toEstimatedSeconds(Analysis analysis, BarMetrics barMetrics) {
+            if (barMetrics == null) {
+                return null;
+            }
+
+            int barCount = analysis.getEndBar() - analysis.getStartBar() + 1;
+            return (int) Math.round(barCount * barMetrics.barDurationMs() / 1_000D);
+        }
     }
 }
diff --git a/src/main/java/com/mr/domain/history/service/HistoryService.java b/src/main/java/com/mr/domain/history/service/HistoryService.java
index 47a1272f..97009226 100644
--- a/src/main/java/com/mr/domain/history/service/HistoryService.java
+++ b/src/main/java/com/mr/domain/history/service/HistoryService.java
@@ -3,6 +3,8 @@
 import com.mr.domain.analysis.entity.Analysis;
 import com.mr.domain.analysis.entity.enums.AnalysisStatus;
 import com.mr.domain.analysis.repository.AnalysisRepository;
+import com.mr.domain.analysis.service.AnalysisBarCalculator;
+import com.mr.domain.analysis.service.AnalysisBarCalculator.BarMetrics;
 import com.mr.domain.history.dto.req.HistoryPeriod;
 import com.mr.domain.history.dto.res.HistoryDetailResponseDTO;
 import com.mr.domain.history.dto.res.HistoryListResponseDTO;
@@ -39,6 +41,7 @@ public class HistoryService {
     private final PlayingRepository playingRepository;
     private final AnalysisRepository analysisRepository;
     private final S3FileService s3FileService;
+    private final AnalysisBarCalculator analysisBarCalculator;
 
     public HistoryListResponseDTO getHistories(Long userId, int page, int size, HistoryPeriod period) {
         validatePaging(page, size);
@@ -77,7 +80,17 @@ public HistoryDetailResponseDTO getHistoryDetail(Long userId, Long playingId) {
                         playing.getRecordingObjectKey()
                 );
 
-        return HistoryDetailResponseDTO.from(playing, analyses, recordingFileUrl);
+        return HistoryDetailResponseDTO.from(
+                playing, analyses, recordingFileUrl, resolveBarMetrics(playing));
+    }
+
+    // 백킹트랙 정보 불완전 시 조회 실패 대신 마디 관련 필드만 null 처리
+    private BarMetrics resolveBarMetrics(Playing playing) {
+        try {
+            return analysisBarCalculator.calculate(playing);
+        } catch (GeneralException exception) {
+            return null;
+        }
     }
 
     private List<Item> buildItems(
diff --git a/src/test/java/com/mr/domain/history/service/HistoryServiceTest.java b/src/test/java/com/mr/domain/history/service/HistoryServiceTest.java
index 2a0d201b..8d42efcd 100644
--- a/src/test/java/com/mr/domain/history/service/HistoryServiceTest.java
+++ b/src/test/java/com/mr/domain/history/service/HistoryServiceTest.java
@@ -16,6 +16,7 @@
 import com.mr.domain.analysis.entity.enums.AnalysisGrade;
 import com.mr.domain.analysis.entity.enums.AnalysisStatus;
 import com.mr.domain.analysis.repository.AnalysisRepository;
+import com.mr.domain.analysis.service.AnalysisBarCalculator;
 import com.mr.domain.backingtrack.entity.BackingTrack;
 import com.mr.domain.history.dto.req.HistoryPeriod;
 import com.mr.domain.history.dto.res.HistoryDetailResponseDTO;
@@ -57,7 +58,8 @@ class HistoryServiceTest {
 
     @BeforeEach
     void setUp() {
-        historyService = new HistoryService(playingRepository, analysisRepository, s3FileService);
+        historyService = new HistoryService(
+                playingRepository, analysisRepository, s3FileService, new AnalysisBarCalculator());
     }
 
     private Playing mockPlaying(Long playingId, Long userId, PlayingStatus status, LocalDateTime endedAt) {
@@ -282,6 +284,8 @@ void getHistoryDetail_success_returnsAllAnalysesRegardlessOfStatus() {
         given(s3FileService.createPresignedDownload(1L, recordingObjectKey)).willReturn(recordingFileUrl);
         given(playing.getBackingTrack()).willReturn(backingTrack);
         given(backingTrack.getAudioFileUrl()).willReturn(backingTrackAudioFileUrl);
+        given(backingTrack.getTimeSignature()).willReturn("4/4");
+        given(backingTrack.getPlaytimeSec()).willReturn(120);
         given(playingRepository.findByIdWithBackingTrack(1L)).willReturn(Optional.of(playing));
 
         Analysis completed = completedAnalysis(1L, 90);
@@ -301,4 +305,44 @@ void getHistoryDetail_success_returnsAllAnalysesRegardlessOfStatus() {
         assertThat(response.analyses()).hasSize(2);
         assertThat(response.analyses().get(1).status()).isEqualTo(AnalysisStatus.PENDING);
     }
+
+    @Test
+    @DisplayName("getHistoryDetail - BPM/박자/재생시간이 있으면 totalBars와 구간별 estimatedSeconds를 계산한다")
+    void getHistoryDetail_success_calculatesBarMetrics() {
+        Playing playing = mockPlaying(1L, 1L, PlayingStatus.COMPLETED, LocalDateTime.now());
+        BackingTrack backingTrack = mock(BackingTrack.class);
+        given(playing.getBackingTrack()).willReturn(backingTrack);
+        given(backingTrack.getTimeSignature()).willReturn("4/4");
+        given(backingTrack.getPlaytimeSec()).willReturn(120);
+        given(playingRepository.findByIdWithBackingTrack(1L)).willReturn(Optional.of(playing));
+
+        Analysis completed = completedAnalysis(1L, 90);
+        given(analysisRepository.findByPlayingIdAndUserIdOrderByStartBarAscIdAsc(1L, 1L))
+                .willReturn(List.of(completed));
+
+        HistoryDetailResponseDTO response = historyService.getHistoryDetail(1L, 1L);
+
+        // BPM 120, 4/4 -> 마디당 2초, 재생 120초 -> 60마디 / 1~8마디 분석 -> 16초
+        assertThat(response.totalBars()).isEqualTo(60);
+        assertThat(response.analyses().get(0).estimatedSeconds()).isEqualTo(16);
+    }
+
+    @Test
+    @DisplayName("getHistoryDetail - 마디 계산 정보가 없으면 조회는 성공하고 마디 관련 필드만 null이다")
+    void getHistoryDetail_missingBarMetrics_returnsNullBarFields() {
+        Playing playing = mockPlaying(1L, 1L, PlayingStatus.COMPLETED, LocalDateTime.now());
+        BackingTrack backingTrack = mock(BackingTrack.class);
+        given(playing.getBackingTrack()).willReturn(backingTrack);
+        given(backingTrack.getPlaytimeSec()).willReturn(null);
+        given(playingRepository.findByIdWithBackingTrack(1L)).willReturn(Optional.of(playing));
+
+        Analysis completed = completedAnalysis(1L, 90);
+        given(analysisRepository.findByPlayingIdAndUserIdOrderByStartBarAscIdAsc(1L, 1L))
+                .willReturn(List.of(completed));
+
+        HistoryDetailResponseDTO response = historyService.getHistoryDetail(1L, 1L);
+
+        assertThat(response.totalBars()).isNull();
+        assertThat(response.analyses().get(0).estimatedSeconds()).isNull();
+    }
 }