diff --git a/src/Core/Application/DTOs/ReportDtos.cs b/src/Core/Application/DTOs/ReportDtos.cs
index 5ffed47..e844c39 100644
--- a/src/Core/Application/DTOs/ReportDtos.cs
+++ b/src/Core/Application/DTOs/ReportDtos.cs
@@ -6,6 +6,7 @@ public sealed class MetricRequestDto
     public string Column        { get; set; } = "C-6111";
     public string Metric        { get; set; } = "";          // energy_efficiency | yield | control_residual
     public DateTime PeriodDateKst { get; set; }              // 운전원이 고른 KST 날짜(00:00 기준)
+    public string Period        { get; set; } = "DAILY";     // DAILY | MONTHLY | YEARLY — 윈도 = PeriodDateKst가 속한 일/월/연
     public string SourceTable   { get; set; } = "history_table"; // | fast_record
     public int?   SessionId     { get; set; }                // fast_record일 때
 }
@@ -23,6 +24,7 @@ public sealed class MetricResultDto
 
     // ── 해상도-인지 메타 ──
     public string  Source     { get; set; } = ""; // history_table | fast_record
+    public string  Period     { get; set; } = "DAILY"; // DAILY | MONTHLY | YEARLY (집계 윈도)
     public int     SamplingMs { get; set; }       // 60000(history) | fast_session.sampling_ms
     public int     N          { get; set; }       // 클린 후 표본수
     public double  CleanedFraction { get; set; }  // 제거된 비율(0~1)
diff --git a/src/Hc900Crawler/Controllers/ReportController.cs b/src/Hc900Crawler/Controllers/ReportController.cs
index 61abfb9..0f23ac3 100644
--- a/src/Hc900Crawler/Controllers/ReportController.cs
+++ b/src/Hc900Crawler/Controllers/ReportController.cs
@@ -125,17 +125,17 @@ GROUP BY b ORDER BY b";
     /// <summary>웹에서 바로 보기 — 한 컬럼·날짜의 전 메트릭을 한 번에.</summary>
     [HttpGet("summary")]
     public async Task<IActionResult> Summary(string column = "C-6111", DateTime? date = null,
-        string source = "history_table", int? sessionId = null, CancellationToken ct = default)
+        string source = "history_table", string period = "DAILY", int? sessionId = null, CancellationToken ct = default)
     {
         var d = (date ?? DateTime.UtcNow.AddHours(9).AddDays(-1)).Date;   // 기본 = 어제(KST)
         var results = new List<MetricResultDto>();
         foreach (var m in SUMMARY_METRICS)
             results.Add(await _metrics.ComputeAsync(new MetricRequestDto
             {
-                Column = column, Metric = m, PeriodDateKst = d,
+                Column = column, Metric = m, PeriodDateKst = d, Period = period,
                 SourceTable = source, SessionId = sessionId
             }, ct));
-        return Ok(new { Column = column, Date = d.ToString("yyyy-MM-dd"), Source = source, Metrics = results });
+        return Ok(new { Column = column, Date = d.ToString("yyyy-MM-dd"), Source = source, Period = period, Metrics = results });
     }
 
     /// <summary>엑셀 템플릿 등록.</summary>
diff --git a/src/Hc900Crawler/wwwroot/js/reports.js b/src/Hc900Crawler/wwwroot/js/reports.js
index 327fde1..65daadc 100644
--- a/src/Hc900Crawler/wwwroot/js/reports.js
+++ b/src/Hc900Crawler/wwwroot/js/reports.js
@@ -25,7 +25,7 @@ paneInit['reports'] = function () {
   if (go) go.onclick = async () => {
     out.innerHTML = '<span class="mono">⏳ 조회 중...</span>';
     try {
-      let url = `/api/report/summary?column=${encodeURIComponent(col.value)}&date=${date.value}&source=${$('rvSource').value}`;
+      let url = `/api/report/summary?column=${encodeURIComponent(col.value)}&date=${date.value}&source=${$('rvSource').value}&period=${$('rvPeriod').value}`;
       if ($('rvSource').value === 'fast_record' && $('rvSess').value) url += `&sessionId=${$('rvSess').value}`;
       const r = await fetch(url);
       if (!r.ok) throw new Error('조회 실패 ' + r.status);
@@ -73,7 +73,8 @@ function rpVal(m, kind) { return m.Status === 'ok' && m.Value != null ? rpFmt(m.
 function renderSummary(d) {
   const by = {}; (d.Metrics || []).forEach(m => by[m.Metric] = m);
   const cl = by['mass_balance_closure'];
-  let html = `<div class="mono" style="margin-bottom:10px;color:var(--t2)">${d.Column} · ${d.Date} · ${d.Source}</div>`;
+  const pTxt = { DAILY: '일', MONTHLY: '월', YEARLY: '연' }[d.Period] || d.Period || '일';
+  let html = `<div class="mono" style="margin-bottom:10px;color:var(--t2)">${d.Column} · ${d.Date} · ${pTxt} · ${d.Source}</div>`;
 
   // 물질수지 신뢰블록
   if (cl) {
diff --git a/src/Hc900Crawler/wwwroot/panes/reports.html b/src/Hc900Crawler/wwwroot/panes/reports.html
index 623abc5..735047b 100644
--- a/src/Hc900Crawler/wwwroot/panes/reports.html
+++ b/src/Hc900Crawler/wwwroot/panes/reports.html
@@ -20,6 +20,13 @@
     <div style="display:flex;gap:10px;align-items:flex-end;flex-wrap:wrap">
       <label>컬럼<br><select id="rvCol" style="margin-top:4px"></select></label>
       <label>날짜(KST)<br><input type="date" id="rvDate" style="margin-top:4px"></label>
+      <label>기간<br>
+        <select id="rvPeriod" style="margin-top:4px">
+          <option value="DAILY">일</option>
+          <option value="MONTHLY">월</option>
+          <option value="YEARLY">연</option>
+        </select>
+      </label>
       <label>소스<br>
         <select id="rvSource" style="margin-top:4px">
           <option value="history_table">history (60초)</option>
@@ -67,6 +74,10 @@
 ■ PV 기반 (근사)
 {{ metric=control_residual; column=C-6111 }}              → 평균 잔차(PV-SP)
 {{ metric=control_residual; column=C-6111; field=sd }}    → 잔차 표준편차
+
+■ 집계 기간 (period, 미지정=DAILY) — 선택 날짜가 속한 일/월/연 전체
+{{ metric=production_total; column=C-6111; period=MONTHLY }}  → 그 달 생산량 적산
+{{ metric=production_total; column=C-6111; period=YEARLY }}   → 그 해 생산량 적산
       </pre>
     </details>
   </section>
diff --git a/src/Infrastructure/Reporting/ReportFillService.cs b/src/Infrastructure/Reporting/ReportFillService.cs
index 597f58c..4ac742d 100644
--- a/src/Infrastructure/Reporting/ReportFillService.cs
+++ b/src/Infrastructure/Reporting/ReportFillService.cs
@@ -40,6 +40,7 @@ public sealed class ReportFillService
                     Metric = kv.GetValueOrDefault("metric", ""),
                     Column = kv.GetValueOrDefault("column", "C-6111"),
                     PeriodDateKst = periodKst,
+                    Period = kv.GetValueOrDefault("period", "DAILY"),   // 셀별 일/월/연 윈도(미지정=일)
                     SourceTable = sourceTable,
                     SessionId = sessionId
                 };
@@ -50,10 +51,10 @@ public sealed class ReportFillService
                 else { cell.Value = m.Status == "no_data" ? "N/A" : "ERR"; anyErr = true; }
 
                 if (cell.Comment == null)
-                    cell.AddComment($"{m.Metric} | src={m.Source} {m.SamplingMs}ms | n={m.N} | keep={1 - m.CleanedFraction:P0} | {m.Unit}"
+                    cell.AddComment($"{m.Metric} | {m.Period} | src={m.Source} {m.SamplingMs}ms | n={m.N} | keep={1 - m.CleanedFraction:P0} | {m.Unit}"
                                     + (m.Error != null ? $" | {m.Error}" : ""), "report");
 
-                cells.Add(new { sheet = ws.Name, r, c, m.Metric, m.Column,
+                cells.Add(new { sheet = ws.Name, r, c, m.Metric, m.Column, m.Period,
                                 field = kv.GetValueOrDefault("field", ""), value = v, m.Status,
                                 m.Source, m.SamplingMs, m.N, m.Unit });
             }
diff --git a/src/Infrastructure/Reporting/ReportMetricService.cs b/src/Infrastructure/Reporting/ReportMetricService.cs
index c895d5d..d70de7e 100644
--- a/src/Infrastructure/Reporting/ReportMetricService.cs
+++ b/src/Infrastructure/Reporting/ReportMetricService.cs
@@ -30,21 +30,41 @@ public sealed class ReportMetricService : IReportMetricService
     private static readonly HashSet<string> SERIES_SOURCES =
         new() { "history_table", "history_1s", "history_1min_src" };
 
+    private static readonly HashSet<string> PERIODS =
+        new(StringComparer.OrdinalIgnoreCase) { "DAILY", "MONTHLY", "YEARLY" };
+
+    /// <summary>KST 날짜가 속한 일/월/연 경계 [from, to) 를 UTC로. recorded_at(UTC) 비교용.</summary>
+    private static (DateTime fromUtc, DateTime toUtc) PeriodWindowUtc(DateTime dateKst, string period)
+    {
+        var d = dateKst.Date;
+        var (fromKst, toKst) = period switch
+        {
+            "MONTHLY" => (new DateTime(d.Year, d.Month, 1), new DateTime(d.Year, d.Month, 1).AddMonths(1)),
+            "YEARLY"  => (new DateTime(d.Year, 1, 1),       new DateTime(d.Year, 1, 1).AddYears(1)),
+            _         => (d,                                d.AddDays(1)),
+        };
+        return (DateTime.SpecifyKind(fromKst, DateTimeKind.Unspecified).AddHours(-9),
+                DateTime.SpecifyKind(toKst,   DateTimeKind.Unspecified).AddHours(-9));
+    }
+
     public async Task<MetricResultDto> ComputeAsync(MetricRequestDto req, CancellationToken ct = default)
     {
         bool isFast = req.SourceTable == "fast_record";
         // history_table(60s) | history_1s(1s 버퍼) | history_1min_src(연속집계) | fast_record. 미지정/미허용→history_table.
         string tbl  = isFast ? "fast_record"
                     : SERIES_SOURCES.Contains(req.SourceTable) ? req.SourceTable : "history_table";
+        string period = string.IsNullOrWhiteSpace(req.Period) ? "DAILY" : req.Period.Trim().ToUpperInvariant();
         var res = new MetricResultDto
         {
-            Metric = req.Metric, Column = req.Column,
+            Metric = req.Metric, Column = req.Column, Period = period,
             Source = tbl, SamplingMs = isFast ? 0 : (tbl == "history_1s" ? 1000 : 60000)
         };
+        // 결정론 게이트: 오타 period를 daily로 묵인하면 틀린 값 → 명시적 에러.
+        if (!PERIODS.Contains(period))
+        { res.Status = "error"; res.Error = $"미지원 period: {req.Period} (DAILY|MONTHLY|YEARLY)"; res.Value = null; return res; }
 
-        // KST 날짜 [00:00, +1d) → UTC (recorded_at은 UTC)
-        var fromUtc = DateTime.SpecifyKind(req.PeriodDateKst.Date, DateTimeKind.Unspecified).AddHours(-9);
-        var toUtc   = fromUtc.AddDays(1);
+        // PeriodDateKst가 속한 일/월/연 [from, to) KST → UTC (recorded_at은 UTC). fast_record는 session 기준이라 윈도 무관.
+        var (fromUtc, toUtc) = PeriodWindowUtc(req.PeriodDateKst, period);
 
         try
         {