ButterflyMX vs DoorKing for Bay Area Properties: An Installer's Comparison

What is the difference between ButterflyMX and DoorKing?

ButterflyMX is a touchscreen video intercom that connects to the building's internet and to the resident's smartphone. Its product page says residents see and speak with visitors on their smartphone before letting them in, and that the call starts as one-way video until the resident turns on their own camera.

DoorKing's 1835 and 1837 are telephone entry systems. A visitor scrolls the directory with the A and Z scroll buttons and presses the One Touch CALL button; the resident can receive the call on a mobile phone number and grant access. The 1835 has a single-line, 20-character LCD directory; the 1837 has an eight-line display with half-inch characters.

Residents on ButterflyMX can also enter with a 6-digit PIN, a fob or a key card, and the property can send visitors a QR code pass. The DoorKing 1835 stores up to 8000 device (card) codes and has two 26-bit Wiegand inputs.

DoorKing also makes video entry systems. The 2112 eVolve is a residential unit for up to 10 residents and three entry points. DoorKing's 2137 cut sheet lists a 6.50 in W x 4.875 in H full-color display and support for 10,000 users.

Elwin installs, configures and supports video intercoms and telephone entry systems for multifamily, mixed-use and commercial properties in the San Francisco Bay Area, and works with both brands. See ButterflyMX video intercom installation for how a ButterflyMX scope is planned.

Wiring, power and what a swap can reuse

ButterflyMX's installation guide says the intercom can only operate doors that have electric locking hardware installed, such as an electric strike, magnetic lock, automatic door or electrified panic bar. A DoorKing 1835 or 1837 has three form C dry contact relays.

The Ethernet run from the intercom to the internet router is CAT5e or higher. A lock run that is already 18/2 matches the cable the diagram specifies, and ButterflyMX's cut sheet lists Ethernet, Wi-Fi, point-to-point and cellular router connectivity.

The 24 VDC power run is gauged by distance: 18 AWG to 50 feet, 16 AWG to 100 feet, 14 AWG to 180 feet and 12 AWG to 300 feet, with a junction box suggested beyond 200 feet. A diode (DC) or varistor (AC) is required when wiring directly to a door strike, and ButterflyMX supplies one 1N400X Series diode and one MOV varistor per intercom. The relay can also land on the REX input of a third-party access control panel if one is present.

ButterflyMX requires the use of its provided 24 VDC power supply and lists minimum UPS requirements of 600VA / 300W. Its recommended device is the APC BE600M1 Back-UPS, and installing without a UPS voids the warranty. A DoorKing 1835 90 Series ships with two 16 VAC, 20 VA transformers, and DoorKing's two-year limited warranty (Rev 11-23) lists external accessory transformers as normal maintenance items that are not covered.

• ButterflyMX's installation guide notes that some installations, especially retrofits, require customized housing.
• Measure the old cabinet before choosing a size.

What each system costs

The cited ButterflyMX cost page lists software at $30-$42 per apartment unit per year; cost depends on the integrations and features added. Commercial and office pricing is set by employee count instead.

Ask a DoorKing dealer for a current quote.

DoorKing's January 2026 subscription schedule lists DKS Cellular voice and data plans from $49.95 a month for up to 100 voice minutes and up to 6 data transfers. The schedule also lists a VoIP + Data plan for use with the 2334-080 for voice and data connections.

DKS Cloud programming is included with those subscriptions, and the schedule says legacy telephone entry systems do not require a Cloud account to be serviceable. DoorKing's 1830 90 Series brochure describes avoiding DKS subscription fees by using the 1830-185 TCP/IP adapter with your own VoIP provider, which requires manual setup by an IT technician and whose compatibility DoorKing says it does not guarantee.

Installation is quoted per entry after a site walk. The lock, cable run and power work at the door are described in access control cost per door.

Warranty, installer requirements and support

ButterflyMX says its intercoms are installed by a local low-voltage installer and that only three connections are needed at the building: internet, power and door strike. Its installer documentation page says the two-year warranty is void unless the installer is certified by ButterflyMX, and its installation guide describes that certification as a free online course that should take no more than 30 minutes. Elwin's ButterflyMX-certified technicians install, configure and support ButterflyMX entries across the Bay Area.

ButterflyMX's warranty statement gives end customers two years from the date the product is sold to the end customer for hardware products that malfunction due to defective materials or workmanship. The installation guide says not including a UPS in the installation voids the warranty.

DoorKing's two-year limited warranty (Rev 11-23) warrants listed products, including Telephone Entry System models 1833, 1834 and 1835, to be free from defects in material and workmanship under normal use and service for two years after the date of purchase by the original customer. The warranty says batteries, light bulbs, LED light bulbs and light strips and external accessory transformers are considered normal maintenance items and are not covered.

Customer software programming support (phone, chat, email) is included with any DoorKing subscription account. ButterflyMX includes live phone or email support in its software fee.

Elwin installs, repairs, replaces and configures both brands, with a single accountable point of contact from site walk through installation and support.

Which one fits your property

Wired internet or a short Ethernet run to the entry, residents who will use an app, and a budget for a per-unit software fee point to ButterflyMX. No internet at a gate, residents who want the panel to ring their telephone number, or a bank of existing readers on a DoorKing controller point to a 1835 or 1837 on DKS Cellular. DoorKing says one cellular box connects up to two systems, and its cellular cut sheet says the cell line can be split for guard tower/dual entry.

ButterflyMX is a video intercom, and DoorKing's 2112 eVolve is a residential video entry system for up to 10 residents. DoorKing's 2137 cut sheet lists apartment buildings among its applications, and the subscription schedule lists its DKS Cloud and per-unit fees.

Before deciding, have these answers ready for the site walk:

• Whether there is internet at the entry, and whether a speed test there shows at least 2 Mbps up and down (ButterflyMX's minimum).
• Whether AT&T 4G LTE coverage reaches the panel location. DoorKing offers DKS Cellular on AT&T 4G-LTE where available.
• Unit count, since ButterflyMX software and DoorKing's 2137 cloud fee are both billed per unit.
• How many readers, gates and elevators the panel must control. A DoorKing 1835 or 1837 expands to 48 wired entry points with Tracker Expansion Board(s); a ButterflyMX intercom has four dry contact relays.
• Whether the old lock wiring is 18/2 that tests good, and where the nearest outlet for a UPS is.

Questions about ButterflyMX and DoorKing