diff --git a/jinja2cli/cli.py b/jinja2cli/cli.py
index dc24495..a97d7a3 100644
--- a/jinja2cli/cli.py
+++ b/jinja2cli/cli.py
@@ -242,12 +242,13 @@ def _load_json5():
 }
 
 
-def render(template_path, data, extensions, strict=False):
+def render(template_path, data, extensions, strict=False, stream=False):
     from jinja2 import (
         __version__ as jinja_version,
         Environment,
         FileSystemLoader,
         StrictUndefined,
+        BaseLoader,
     )
 
     # Starting with jinja2 3.1, `with_` and `autoescape` are no longer
@@ -262,7 +263,7 @@ def render(template_path, data, extensions, strict=False):
                 extensions.append(ext)
 
     env = Environment(
-        loader=FileSystemLoader(os.path.dirname(template_path)),
+        loader=BaseLoader() if stream else FileSystemLoader(os.path.dirname(template_path)),
         extensions=extensions,
         keep_trailing_newline=True,
     )
@@ -273,7 +274,8 @@ def render(template_path, data, extensions, strict=False):
     env.globals["environ"] = lambda key: force_text(os.environ.get(key))
     env.globals["get_context"] = lambda: data
 
-    return env.get_template(os.path.basename(template_path)).render(data)
+    template = env.from_string(template_path.read()) if stream else env.get_template(os.path.basename(template_path))
+    return template.render(data)
 
 
 def is_fd_alive(fd):
@@ -285,53 +287,57 @@ def is_fd_alive(fd):
 
 
 def cli(opts, args):
-    template_path, data = args
-    format = opts.format
-    if data in ("-", ""):
-        if data == "-" or (data == "" and is_fd_alive(sys.stdin)):
-            data = sys.stdin.read()
-        if format == "auto":
-            # default to yaml first if available since yaml
-            # is a superset of json
-            if has_format("yaml"):
-                format = "yaml"
-            else:
-                format = "json"
-    else:
-        path = os.path.join(os.getcwd(), os.path.expanduser(data))
-        if format == "auto":
-            ext = os.path.splitext(path)[1][1:]
-            if has_format(ext):
-                format = ext
-            else:
-                raise InvalidDataFormat(ext)
-
-        with open(path) as fp:
-            data = fp.read()
-
-    template_path = os.path.abspath(template_path)
-
-    if data:
-        try:
-            fn, except_exc, raise_exc = get_format(format)
-        except InvalidDataFormat:
-            if format in ("yml", "yaml"):
-                raise InvalidDataFormat("%s: install pyyaml to fix" % format)
-            if format == "toml":
-                raise InvalidDataFormat("toml: install toml to fix")
-            if format == "xml":
-                raise InvalidDataFormat("xml: install xmltodict to fix")
-            if format == "hjson":
-                raise InvalidDataFormat("hjson: install hjson to fix")
-            if format == "json5":
-                raise InvalidDataFormat("json5: install json5 to fix")
-            raise
-        try:
-            data = fn(data) or {}
-        except except_exc:
-            raise raise_exc("%s ..." % data[:60])
-    else:
+    if opts.stream:
         data = {}
+        template_path = sys.stdin
+    else:
+        template_path, data = args
+        format = opts.format
+        if data in ("-", ""):
+            if data == "-" or (data == "" and is_fd_alive(sys.stdin)):
+                data = sys.stdin.read()
+            if format == "auto":
+                # default to yaml first if available since yaml
+                # is a superset of json
+                if has_format("yaml"):
+                    format = "yaml"
+                else:
+                    format = "json"
+        else:
+            path = os.path.join(os.getcwd(), os.path.expanduser(data))
+            if format == "auto":
+                ext = os.path.splitext(path)[1][1:]
+                if has_format(ext):
+                    format = ext
+                else:
+                    raise InvalidDataFormat(ext)
+
+            with open(path) as fp:
+                data = fp.read()
+
+        template_path = os.path.abspath(template_path)
+
+        if data:
+            try:
+                fn, except_exc, raise_exc = get_format(format)
+            except InvalidDataFormat:
+                if format in ("yml", "yaml"):
+                    raise InvalidDataFormat("%s: install pyyaml to fix" % format)
+                if format == "toml":
+                    raise InvalidDataFormat("toml: install toml to fix")
+                if format == "xml":
+                    raise InvalidDataFormat("xml: install xmltodict to fix")
+                if format == "hjson":
+                    raise InvalidDataFormat("hjson: install hjson to fix")
+                if format == "json5":
+                    raise InvalidDataFormat("json5: install json5 to fix")
+                raise
+            try:
+                data = fn(data) or {}
+            except except_exc:
+                raise raise_exc("%s ..." % data[:60])
+        else:
+            data = {}
 
     extensions = []
     for ext in opts.extensions:
@@ -362,7 +368,7 @@ def cli(opts, args):
 
         out = codecs.getwriter("utf8")(out)
 
-    out.write(render(template_path, data, extensions, opts.strict))
+    out.write(render(template_path, data, extensions, opts.strict, opts.stream))
     out.flush()
     return 0
 
@@ -461,12 +467,18 @@ def main():
         metavar="FILE",
         action="store",
     )
+    parser.add_option(
+        "-S",
+        "--stream",
+        help="Input template comes from stdin. There is no input data argument",
+        action="store_true",
+    )
     opts, args = parser.parse_args()
 
     # Dedupe list
     opts.extensions = set(opts.extensions)
 
-    if len(args) == 0:
+    if len(args) == 0 and not opts.stream:
         parser.print_help()
         sys.exit(1)