diff --git a/README.md b/README.md
index d313e27..c17189f 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ CLI tool to track and display [OpenCode](https://github.com/opencodeco/opencode)
 ## Features
 
 - **Daily breakdown** — token usage and cost per day
-- **Group by dimension** — model, agent, provider, or session
+- **Group by dimension** — minute/hour/day/week/month time buckets, or model, agent, provider, session
 - **Agent × Model view** — see which model each agent uses
 - **Time filtering** — last N days, relative durations (`7d`, `2w`), or ISO dates
 - **Period comparison** — compare current vs previous period with `--compare`
@@ -46,10 +46,13 @@ opencode-usage
 
 # Time filtering
 opencode-usage run --days 30
+opencode-usage run --weeks 2
+opencode-usage run --months 6
 opencode-usage run --since 7d
 opencode-usage run --since 2025-01-01
 
-# Group by dimension
+# Group by dimension (time buckets or entities)
+opencode-usage run --by hour           # minute, hour, day, week, month
 opencode-usage run --by model
 opencode-usage run --by agent          # shows model per agent
 opencode-usage run --by provider
diff --git a/src/opencode_usage/cli.py b/src/opencode_usage/cli.py
index d0192a7..747bc06 100644
--- a/src/opencode_usage/cli.py
+++ b/src/opencode_usage/cli.py
@@ -11,7 +11,7 @@
 
 from . import __version__, render
 from .db import OpenCodeDB, UsageRow
-from .render import render_daily, render_grouped, render_summary
+from .render import render_grouped, render_summary, render_time
 
 
 def _parse_since(value: str) -> datetime:
@@ -41,20 +41,34 @@ def _parse_since(value: str) -> datetime:
 
 
 def _add_time_args(parser: argparse.ArgumentParser) -> None:
-    """Add --days and --since to *parser* (shared by run & insights)."""
+    """Add time-window flags to *parser* (shared by run & insights)."""
     parser.add_argument(
         "--days",
         type=int,
         default=None,
         metavar="N",
-        help="Show last N days (default: 7)",
+        help="Show the last N days (default: 7)",
+    )
+    parser.add_argument(
+        "--weeks",
+        type=int,
+        default=None,
+        metavar="N",
+        help="Show the last N weeks",
+    )
+    parser.add_argument(
+        "--months",
+        type=int,
+        default=None,
+        metavar="N",
+        help="Show the last N months (30 days each)",
     )
     parser.add_argument(
         "--since",
         type=_parse_since,
         default=None,
         metavar="SPEC",
-        help="Time filter: '7d', '2w', '30d', '3h', or ISO date",
+        help="Time filter: '7d', '2w', '30d', '3h', '12m', or ISO date",
     )
 
 
@@ -72,9 +86,12 @@ def _build_parser() -> argparse.ArgumentParser:
     _add_time_args(run_p)
     run_p.add_argument(
         "--by",
-        choices=["model", "agent", "provider", "session", "day"],
+        choices=["minute", "hour", "day", "week", "month", "model", "agent", "provider", "session"],
         default=None,
-        help="Group results by dimension",
+        help=(
+            "Group by minute, hour, day, week, month, model, agent, provider, "
+            "or session"
+        ),
     )
     run_p.add_argument(
         "--limit",
@@ -126,6 +143,9 @@ def _build_parser() -> argparse.ArgumentParser:
     return p
 
 
+_TIME_GROUPINGS = ("minute", "hour", "day", "week", "month")
+
+
 def _resolve_since(args: argparse.Namespace) -> tuple[datetime | None, str]:
     """Resolve the effective 'since' datetime and a human-readable period label."""
     now = datetime.now().astimezone()
@@ -133,9 +153,19 @@ def _resolve_since(args: argparse.Namespace) -> tuple[datetime | None, str]:
     if args.since is not None:
         return args.since, f"Since {args.since.strftime('%Y-%m-%d')}"
 
-    if args.days is not None:
-        since = now - timedelta(days=args.days)
-        return since, f"Last {args.days} days"
+    for value, label in (
+        (args.days, "days"),
+        (getattr(args, "weeks", None), "weeks"),
+        (getattr(args, "months", None), "months"),
+    ):
+        if value is not None and value > 0:
+            if label == "weeks":
+                delta = timedelta(days=value * 7)
+            elif label == "months":
+                delta = timedelta(days=value * 30)
+            else:
+                delta = timedelta(days=value)
+            return now - delta, f"Last {value} {label}"
 
     since = now - timedelta(days=7)
     return since, "Last 7 days"
@@ -150,8 +180,8 @@ def _fetch_rows(
     limit: int | None = None,
 ) -> list[UsageRow]:
     """Fetch rows based on group_by dimension."""
-    if group_by == "day":
-        return db.daily(since=since, until=until, limit=limit)
+    if group_by in _TIME_GROUPINGS:
+        return db.by_time(group_by, since=since, until=until, limit=limit)
     if group_by == "model":
         return db.by_model(since=since, until=until, limit=limit)
     if group_by == "agent":
@@ -229,8 +259,8 @@ def _cmd_run(args: argparse.Namespace) -> None:
 
     deltas = _compute_deltas(rows, prev_rows) if prev_rows else None
 
-    if group_by == "day":
-        render_daily(rows, period)
+    if group_by in _TIME_GROUPINGS:
+        render_time(rows, period, granularity=group_by)
     else:
         render_grouped(rows, group_by, period, deltas=deltas)
 
diff --git a/src/opencode_usage/db.py b/src/opencode_usage/db.py
index 7e1711b..09cd961 100644
--- a/src/opencode_usage/db.py
+++ b/src/opencode_usage/db.py
@@ -38,6 +38,28 @@ class UsageRow:
     detail: str | None = None
 
 
+_TIME_FORMATS = {
+    "minute": "%Y-%m-%d %H:%M",
+    "hour": "%Y-%m-%d %H:00",
+    "day": "%Y-%m-%d",
+    "week": "%Y-W%W",
+    "month": "%Y-%m",
+}
+
+
+@dataclass
+class Filters:
+    """Row filters applied to every query (all fields are optional).
+
+    The row-filters feature uses this; it is inert until then.
+    """
+
+    providers: list[str] | None = None
+    models: list[str] | None = None
+    agents: list[str] | None = None
+    exclude_providers: list[str] | None = None
+
+
 @dataclass
 class SessionMeta:
     """Metadata about a user session."""
@@ -151,22 +173,43 @@ def _base_query(
 
     # ── public API ────────────────────────────────────────────────
 
-    def daily(
+    def by_time(
         self,
+        granularity: str = "day",
         since: datetime | None = None,
         until: datetime | None = None,
         limit: int | None = None,
+        filters: Filters | None = None,
     ) -> list[UsageRow]:
+        """Group by a time bucket: minute, hour, day, week, or month.
+
+        ``filters`` is forwarded to the query layer once row filters land
+        (tracked in the filters-and-output PR); it is inert here.
+        """
+        fmt = _TIME_FORMATS.get(granularity, _TIME_FORMATS["day"])
+        kwargs: dict[str, object] = {}
+        if filters is not None:
+            kwargs["filters"] = filters
         return self._base_query(
             group_expr=(
-                "date(json_extract(data, '$.time.created') / 1000, 'unixepoch', 'localtime')"
+                f"strftime('{fmt}', json_extract(data, '$.time.created') / 1000, "
+                "'unixepoch', 'localtime')"
             ),
             since=since,
             until=until,
             order="label DESC",
             limit=limit,
+            **kwargs,
         )
 
+    def daily(
+        self,
+        since: datetime | None = None,
+        until: datetime | None = None,
+        limit: int | None = None,
+    ) -> list[UsageRow]:
+        return self.by_time("day", since=since, until=until, limit=limit)
+
     def by_model(
         self,
         since: datetime | None = None,
diff --git a/src/opencode_usage/render.py b/src/opencode_usage/render.py
index db9ebb9..7bf451d 100644
--- a/src/opencode_usage/render.py
+++ b/src/opencode_usage/render.py
@@ -195,12 +195,22 @@ def render_summary(
     console.print(Panel(text, title=f"[bold]OpenCode Usage — {period}[/bold]", border_style="blue"))
 
 
-def render_daily(rows: list[UsageRow], period: str) -> None:
-    """Render the daily breakdown table."""
+_TIME_LABELS = {
+    "minute": "Minute",
+    "hour": "Hour",
+    "day": "Date",
+    "week": "Week",
+    "month": "Month",
+}
+
+
+def render_time(rows: list[UsageRow], period: str, granularity: str = "day") -> None:
+    """Render the time-bucketed breakdown table."""
+    label = _TIME_LABELS.get(granularity, "Bucket")
     trend = [r.tokens.total for r in rows]
     table = _make_table(
-        title=f"Daily Usage ({period})",
-        label_header="Date",
+        title=f"{label} Usage ({period})",
+        label_header=label,
         rows=rows,
         show_breakdown=True,
         trend_values=trend,
@@ -208,6 +218,11 @@ def render_daily(rows: list[UsageRow], period: str) -> None:
     console.print(table)
 
 
+def render_daily(rows: list[UsageRow], period: str) -> None:
+    """Render the daily breakdown table (legacy alias of render_time)."""
+    render_time(rows, period, granularity="day")
+
+
 def render_grouped(
     rows: list[UsageRow],
     group_by: str,
diff --git a/tests/test_cli.py b/tests/test_cli.py
index 6715502..6ee8c39 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -326,3 +326,49 @@ def test_unknown_group_returns_empty(self, tmp_path):
         db = OpenCodeDB(db_path=_make_cli_db(tmp_path))
         rows = _fetch_rows(db, "unknown")
         assert rows == []
+
+
+# ── --weeks / --months and extended --by ─────────────────────
+
+
+class TestWeeksMonthsFlags:
+    def test_weeks_flag(self):
+        args = _build_parser().parse_args(["run", "--weeks", "2"])
+        assert args.weeks == 2
+
+    def test_months_flag(self):
+        args = _build_parser().parse_args(["run", "--months", "6"])
+        assert args.months == 6
+
+    def test_insights_months_flag(self):
+        args = _build_parser().parse_args(["insights", "--months", "3"])
+        assert args.months == 3
+
+
+class TestTimeGroupings:
+    def test_by_choices_time(self):
+        parser = _build_parser()
+        for choice in ("minute", "hour", "week", "month"):
+            args = parser.parse_args(["run", "--by", choice])
+            assert args.by == choice
+
+
+class TestResolveSinceWeeksMonths:
+    def test_weeks_flag(self):
+        ns = argparse.Namespace(since=None, days=None, weeks=2, months=None)
+        since, period = _resolve_since(ns)
+        expected = datetime.now().astimezone() - timedelta(days=14)
+        assert abs((since - expected).total_seconds()) < 2
+        assert period == "Last 2 weeks"
+
+    def test_months_flag(self):
+        ns = argparse.Namespace(since=None, days=None, weeks=None, months=6)
+        since, period = _resolve_since(ns)
+        expected = datetime.now().astimezone() - timedelta(days=180)
+        assert abs((since - expected).total_seconds()) < 2
+        assert period == "Last 6 months"
+
+    def test_days_wins_over_months(self):
+        ns = argparse.Namespace(since=None, days=7, weeks=None, months=12)
+        _since, period = _resolve_since(ns)
+        assert period == "Last 7 days"
diff --git a/tests/test_db.py b/tests/test_db.py
index 50dd535..0bf1c97 100644
--- a/tests/test_db.py
+++ b/tests/test_db.py
@@ -204,6 +204,43 @@ def test_limit(self, db_path):
         assert len(rows) == 1
 
 
+# ── by_time ──────────────────────────────────────────────────
+
+
+class TestByTime:
+    def test_hour_buckets(self, db_path):
+        db = OpenCodeDB(db_path=db_path)
+        rows = db.by_time("hour")
+        assert rows
+        for r in rows:
+            assert ":" in r.label  # YYYY-MM-DD HH:00
+
+    def test_week_buckets(self, db_path):
+        db = OpenCodeDB(db_path=db_path)
+        rows = db.by_time("week")
+        assert rows
+        for r in rows:
+            assert "-W" in r.label  # YYYY-WNN
+
+    def test_month_buckets(self, db_path):
+        db = OpenCodeDB(db_path=db_path)
+        rows = db.by_time("month")
+        assert rows
+        for r in rows:
+            assert len(r.label) == 7  # YYYY-MM
+
+    def test_unknown_granularity_falls_back_to_day(self, db_path):
+        db = OpenCodeDB(db_path=db_path)
+        rows = db.by_time("decade")
+        assert rows
+        for r in rows:
+            assert "-" in r.label
+
+    def test_daily_is_day_granularity(self, db_path):
+        db = OpenCodeDB(db_path=db_path)
+        assert db.daily() == db.by_time("day")
+
+
 # ── by_model ─────────────────────────────────────────────────