diff --git a/tools/ota_push.py b/tools/ota_push.py
new file mode 100755
index 0000000..c80bf06
--- /dev/null
+++ b/tools/ota_push.py
@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+"""
+ota_push.py — Push firmware OTA to a TimerCamera-F device via Arduino OTA.
+
+Requires: Python 3.8+, no extra pip packages needed
+Device must be connected to WiFi and reachable on the local network.
+
+Usage:
+  python ota_push.py \\
+    --host dc-0042.local \\
+    --firmware firmware/.pio/build/timercam/firmware.bin
+"""
+import argparse
+import hashlib
+import os
+import socket
+import sys
+import time
+
+
+OTA_PORT = 3232
+
+
+def compute_md5(path: str) -> str:
+    h = hashlib.md5()
+    with open(path, "rb") as f:
+        while chunk := f.read(8192):
+            h.update(chunk)
+    return h.hexdigest()
+
+
+def resolve_host(host: str, timeout: float = 10.0) -> str:
+    """Resolve hostname to IP, retrying until timeout."""
+    deadline = time.monotonic() + timeout
+    last_err = None
+    while time.monotonic() < deadline:
+        try:
+            return socket.gethostbyname(host)
+        except socket.gaierror as e:
+            last_err = e
+            time.sleep(0.5)
+    raise RuntimeError(f"Could not resolve {host!r} within {timeout:.0f}s: {last_err}")
+
+
+def push_ota(host: str, firmware_path: str) -> None:
+    size = os.path.getsize(firmware_path)
+    md5  = compute_md5(firmware_path)
+
+    print(f"Resolving {host} ...")
+    ip = resolve_host(host)
+    print(f"  → {ip}")
+
+    print(f"Connecting to {ip}:{OTA_PORT} ...")
+    with socket.create_connection((ip, OTA_PORT), timeout=15) as sock:
+        # Arduino OTA handshake: "0:<size>:<md5>\n"
+        header = f"0:{size}:{md5}\n".encode()
+        sock.sendall(header)
+
+        sock.settimeout(10)
+        resp = sock.recv(64).decode(errors="replace").strip()
+        if resp != "OK":
+            raise RuntimeError(f"OTA handshake rejected: {resp!r}")
+
+        print(f"Sending {size:,} bytes ...")
+        sent = 0
+        with open(firmware_path, "rb") as f:
+            while chunk := f.read(4096):
+                sock.sendall(chunk)
+                sent += len(chunk)
+                pct = sent * 100 // size
+                print(f"\r  {pct:3d}% [{sent:,}/{size:,}]", end="", flush=True)
+        print()
+
+        sock.settimeout(30)
+        final = sock.recv(64).decode(errors="replace").strip()
+        if final != "OK":
+            raise RuntimeError(f"OTA write failed: {final!r}")
+
+    print(f"✓ OTA complete — {host} is rebooting")
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(
+        description="Push OTA firmware update to a door counter device")
+    parser.add_argument("--host",     required=True,
+                        help="mDNS hostname or IP, e.g. dc-0042.local")
+    parser.add_argument("--firmware", required=True,
+                        help="Path to .bin firmware file")
+    args = parser.parse_args()
+
+    if not os.path.exists(args.firmware):
+        print(f"Error: firmware file not found: {args.firmware}", file=sys.stderr)
+        sys.exit(1)
+
+    try:
+        push_ota(args.host, args.firmware)
+    except (RuntimeError, OSError) as e:
+        print(f"\nError: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()