diff --git a/bincio/render/cli.py b/bincio/render/cli.py
index 189f65b..2a2466f 100644
--- a/bincio/render/cli.py
+++ b/bincio/render/cli.py
@@ -43,6 +43,15 @@ def _find_data_dir(explicit: Optional[str], config_path: Optional[str]) -> Path:
         if out:
             return Path(out).expanduser().resolve()
 
+    # Auto-detect: try extract_config.yaml in cwd
+    auto_config = Path.cwd() / "extract_config.yaml"
+    if auto_config.exists():
+        import yaml
+        raw = yaml.safe_load(auto_config.read_text())
+        out = raw.get("output", {}).get("dir")
+        if out:
+            return Path(out).expanduser().resolve()
+
     # Default: ./bincio_data next to cwd
     default = Path.cwd() / "bincio_data"
     if default.exists():