HM Digital
HM Digital is a privately held water testing instrumentation manufacturer, founded in 1987, that designs and produces TDS, pH, EC, ORP meters, monitors, controllers, refractometers, and leak sensors for consumer, commercial, and industrial water quality applications across more than 50 countries.
- Company typePrivate
- Founded1987
- HeadquartersRedondo Beach, United States
- Headcount101–250
- GTM typeB2B and B2C
- OfferingHardware or Manufacturing
What HM Digital does
HM Digital, Inc. is a privately held manufacturer of water testing instrumentation, founded in 1987 as Heemang Electronics and headquartered in Signal Hill, California, with ISO-9001 certified manufacturing facilities in Seoul, South Korea and Qingdao, China. The company designs and produces a broad portfolio of handheld meters (TDS, EC, pH, ORP, salinity), inline monitors (single, dual, and triple-line configurations), industrial controllers with 4-20mA PLC output, digital refractometers for beverage applications, leak block sensors, and a consumable ecosystem of replacement probes and calibration solutions. Its core technology is built around electrochemical sensor measurement with automatic temperature compensation, multiple EC-to-TDS conversion factors, and IP-67 waterproof housings for professional-grade models.
HM Digital operates as a product-led OEM with global distribution, selling through a network of distributors across more than 50 countries and offering private-label/OEM manufacturing services to partners requiring branded water testing products. Its US office, established in 2000, handles marketing, customer service, and distribution for the Americas, Europe, Africa, the Middle East, Australia, and South Asia, while its Korean and Chinese factories support co-designed production and scale manufacturing. Customers span consumer water purification (RO/DI), industrial water treatment (boilers, cooling towers, commercial RO), hydroponics and aquaculture, and beverage production (brewing, winemaking), with the company reporting 101-250 employees globally.
Revenue is generated through hardware sales of meters, monitors, controllers, refractometers, and accessories, supplemented by OEM/private-label contract manufacturing. The company holds ISO-9001 certification for both factories, CE Mark for European market access, and IP-67 ratings for professional products, and has filed US industrial design registration for its AquaPro Series magnetic-body tester. Specific pricing is not publicly disclosed; products are positioned at the value tier of the water testing category and distributed via resellers rather than direct-to-consumer channels.
HM Digital firmographics
Firmographics- Name
- HM Digital
- Legal name
- HM Digital, Inc.
- Website
- https://hmdigital.com
- Company type
- Private
- Founded year
- 1987
- Operating status
- Operating
- Headcount range
- 101–250 employees
- Short description
- HM Digital is a privately held water testing instrumentation manufacturer, founded in 1987, that designs and produces TDS, pH, EC, ORP meters, monitors, controllers, refractometers, and leak sensors for consumer, commercial, and industrial water quality applications across more than 50 countries.
- Ownership category
- akta.pro rank
HM Digital industry classification
Industry- Product category
- Water Quality Testing Instrumentation
- NAICS
- Other Measuring and Controlling Device Manufacturing (334519), Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals (334515), Totalizing Fluid Meter and Counting Device Manufacturing (334514)
- SIC
- Industrial Instruments For Measurement, Display, And Control (3823), Laboratory Analytical Instruments (3826), Totalizing Fluid Meters & Counting Devices (3824)
- akta.pro primary industry
- Sensors & Instrumentation Electronics Manufacturing Services (Transmitters, analyzers, industrial sensors) (IMAGAGAL)
- akta.pro secondary industries
- Monitoring & Control (Dosing Systems, Remote Monitoring, Sensors) (BPABAJAK), Water Testing Kits & Monitoring (Household) (CRAJAJAL), Ruggedized/Harsh-Environment Electronics Manufacturing (IP-rated, shock/vibration, wide-temp) (IMAGAGAF)
Keywords
Where HM Digital is headquartered
LocationHeadquarters
- HQ city
- Redondo Beach
- HQ country
- United States
- HQ region
- North America
Offices3 records
Markets served
HM Digital business model
Business model- GTM type
- B2B and B2C
- Offering type
- Hardware or Manufacturing
- Cost components
- Supply Chain, Operations, Personnel, Technology or R&D, Marketing or Sales, Infrastructure
Revenue model
- Water Testing Instruments Sales: Sale of handheld meters, monitors, controllers, and accessories for water quality testing including TDS meters, pH meters, EC meters, refractometers, and leak block sensors. Products sold to consumers, commercial users, and industrial applications.
- OEM Services and Private Labeling: Customized product manufacturing and private labeling services for distributors and partners requiring branded water testing instrumentation.
Go-to-market motion1 record
Distribution channels2 records
Marketing channels3 records
HM Digital product offering
Product offeringCore offering
HM Digital designs and manufactures water testing instrumentation, including handheld meters (TDS, pH, EC, ORP, salinity), continuous inline monitors, industrial TDS/EC/pH controllers with relay and 4-20mA outputs, digital refractometers (Brix, salt, wine, beer), commercial leak block sensors for RO systems, and accessories such as replacement probes and calibration solutions. The company operates as an OEM with co-design between Los Angeles and ISO-9001 certified factories in Seoul, Korea and Qingdao, China, and sells through a global distributor network in over 50 countries, also offering private label and custom OEM services.
Product overview
HM Digital is a water testing instrumentation manufacturer offering a comprehensive portfolio of handheld meters, monitors, controllers, refractometers, leak block sensors, and accessories. The core product lines include: (1) Handhelds – portable testers for pH, TDS, EC, ORP, and salinity measurements used in hydroponics, aquariums, pools, and water purification; (2) Monitors – continuous and inline monitors including single-line, dual-line, and triple-point systems for tracking feed vs. product water quality; (3) Controllers – industrial-grade TDS/EC and pH controllers with relay outputs for automated dosing and pump/valve control; (4) Refractometers – digital Brix, salt, and beverage refractometers for food and beverage applications; (5) Leak Block Sensors – commercial leak detection for RO systems; (6) Accessories – replacement sensors/probes and calibration solutions/buffers to maintain accuracy. Products are co-designed between Los Angeles and an ISO-9001 certified factory in Seoul, Korea, serving customers in over 50 countries.
Differentiator
Problem solved
Functional benefit
Products and services
- Handhelds
- Monitors
- Controllers
- Refractometers
- Leak Block Sensors
- Accessories
- OEM and Private Label Services
Companies that use HM Digital
Customer profileSegments4 records
Ideal customer profiles4 records
HM Digital technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature5 records
HM Digital partnerships and signals
Strategic signalScale indicators3 records
Recent moves8 records
Expansion highlights6 records
HM Digital competitors and assessment
Company assessmentDirect peers
- Hanna Instruments: Hanna Instruments is a leading global manufacturer of portable and benchtop water quality instrumentation, including pH, EC, TDS, ORP, and ion-specific meters. It directly competes with HM Digital across the handheld and controller product lines for both consumer/hobbyist and industrial customers.
- Milwaukee Instruments: Milwaukee Instruments produces a comparable range of handheld pH, EC, TDS, and ORP meters, as well as controllers and refractometers targeted at hydroponics, aquariums, brewing, and pool/spa applications. Its product positioning and price points overlap directly with HM Digital's handheld and monitor portfolio.
- Bluelab: Bluelab specializes in water quality measurement for hydroponics and horticulture, offering handheld pH, EC, and TDS meters plus continuous monitors. It competes with HM Digital for the hydroponics and agriculture customer segment that HM Digital explicitly serves.
- Apera Instruments: Apera Instruments manufactures portable pH, EC, TDS, and ORP meters and is also headquartered in the US with Asian-sourced manufacturing. It targets overlapping consumer, hydroponics, and laboratory users with competitively priced handheld meters and competes directly with HM Digital's COM and PH product lines.
Broad incumbents
- YSI (a Xylem brand): YSI, part of Xylem, is a major manufacturer of water quality sensors and instruments used for environmental monitoring, aquaculture, and industrial process control. It competes with HM Digital in the industrial controller and continuous monitoring segments, though it operates at much larger scale and broader application breadth.
- Thermo Fisher Scientific: Thermo Fisher supplies laboratory and process water quality instrumentation across pharma, food and beverage, and environmental testing. It overlaps with HM Digital in refractometers (Brix/sugar) and benchtop analytical instruments, though its portfolio spans far beyond water testing.
- Horiba Scientific: Horiba produces high-end analytical and process water quality instruments for laboratory and industrial customers. It competes in selected segments such as refractometry and inline process monitoring, though at a higher price point and broader scope than HM Digital.
- Extech Instruments (FLIR/Teledyne): Extech supplies portable test and measurement instruments including water quality meters and refractometers through industrial distribution channels. Its handheld and combination meter lines overlap with HM Digital's consumer and light-commercial offerings, particularly in HVAC, plumbing, and field service applications.
Emerging players
- Atlas Scientific: Atlas Scientific designs water quality sensor probes and OEM embedded sensing modules for industrial and hobbyist markets. It competes with HM Digital in the OEM/private label and industrial controller space, with a stronger software and embedded engineering orientation.
- Sensorex: Sensorex manufactures pH, ORP, conductivity, and dissolved oxygen sensors and transmitters for industrial water treatment. It overlaps with HM Digital in the industrial controller and probe replacement accessory categories, particularly for OEM and system integrator customers.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat4 records
Key risks6 records
Key highlights6 records
Customer concentration
HM Digital social profiles
Digital presenceHM Digital compliance and trust
Trust signalCompliance4 records
HM Digital financial estimates
Financial estimateRevenue estimate
Valuation estimate
HM Digital leadership team
Management profileNumber of profiles
Profiles1 record
HM Digital funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
HM Digital M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about HM Digital
What does HM Digital do?
HM Digital designs and manufactures water testing instrumentation, including handheld meters (TDS, pH, EC, ORP, salinity), continuous inline monitors, industrial TDS/EC/pH controllers with relay and 4-20mA outputs, digital refractometers (Brix, salt, wine, beer), commercial leak block sensors for RO systems, and accessories such as replacement probes and calibration solutions. The company operates as an OEM with co-design between Los Angeles and ISO-9001 certified factories in Seoul, Korea and Qingdao, China, and sells through a global distributor network in over 50 countries, also offering private label and custom OEM services.
Is HM Digital a public or private company?
HM Digital is a private company. It is classified as founder individual operated bootstrapped and is currently operating.
When was HM Digital founded?
HM Digital was founded in 1987. It employs 101 to 250 people.
Where is HM Digital based?
HM Digital is headquartered in Redondo Beach, United States, in the North America region.
How does HM Digital make money?
Two revenue lines are on record. Water Testing Instruments Sales are the primary driver. The others are OEM Services and Private Labeling.
Who are HM Digital's main competitors?
Direct peers on record are Hanna Instruments, Milwaukee Instruments, Bluelab and Apera Instruments. Broad incumbents are YSI (a Xylem brand), Thermo Fisher Scientific, Horiba Scientific and Extech Instruments (FLIR/Teledyne). Emerging players are Atlas Scientific and Sensorex.
Does HM Digital have an API?
No public API is recorded for HM Digital.
What industry is HM Digital in?
HM Digital's product category is Water Quality Testing Instrumentation. Its primary akta.pro industry code is IMAGAGAL, Sensors & Instrumentation Electronics Manufacturing Services (Transmitters, analyzers, industrial sensors), with a secondary code of BPABAJAK, Monitoring & Control (Dosing Systems, Remote Monitoring, Sensors). Its NAICS code is 334519 and its SIC code is 3823.