Types of CPAP Machines: CPAP vs APAP vs BiPAP

Quick answer: what are the types of CPAP machines?

There are three main types of positive airway pressure machine. CPAP delivers one fixed pressure all night. APAP adjusts automatically within a prescribed range. BiPAP uses a higher pressure to inhale and a lower one to exhale (source: NHLBI). Travel units are miniaturised versions of the first two. For most people with uncomplicated obstructive sleep apnea, AASM recommends either CPAP or APAP (source: AASM).

Key takeaways

CPAP (fixed): one prescribed pressure, the simplest and usually the cheapest option.
APAP (auto-adjusting): varies pressure night to night. AASM strongly recommends that PAP therapy be initiated using either APAP at home or an in-laboratory titration in adults without significant comorbidities (source: AASM).
BiPAP (bilevel): two pressures. AASM suggests CPAP or APAP over bilevel for routine treatment of obstructive sleep apnea, so BiPAP is generally reserved for high pressures, exhalation difficulty, or conditions such as obesity hypoventilation (source: AASM).
Pressure range: adult auto-adjusting devices typically operate between 5 and 15 cm H₂O (source: NIH – StatPearls).
What decides for you: your AHI and titration result, not the marketing. Mild is 5–15 events an hour, moderate above 15 to 30, severe above 30 (source: NIH – StatPearls).

If you’ve been diagnosed with sleep apnea, understanding the different types of CPAP machines available can help you choose the right device for your specific needs.

CPAP therapy remains the gold standard for managing obstructive sleep apnea, and selecting the appropriate machine can significantly impact your sleep quality and treatment success.

What is a CPAP machine?

NHLBI defines it plainly: a machine that “uses mild air pressure to keep breathing airways open while you sleep”, made up of a mask, straps, a connecting tube and a motor (source: NHLBI). Everything below is a variation on how that motor decides what pressure to deliver. For the full mechanics, see what a CPAP machine does.

A CPAP machine promotes steady and uninterrupted breathing during sleep by generating a stream of pressurized air that is sent through a hose and a mask into the upper airway. This continuous airflow prevents the collapse of throat tissues that causes breathing interruptions in people with sleep apnea.

The basic components of any CPAP setup include a motor that generates pressurized air, a hose connecting the machine to your mask, and a mask that seals over your nose or mouth. PAP machines measure pressure in centimeters of water (cm H2O), with most therapeutic settings ranging from 4 to 20 cm H2O.

Standard CPAP machines

Traditional CPAP (continuous positive airway pressure) machines represent the most common type of sleep apnea treatment device. CPAP machines provide constant pressure to keep your upper airway open as you sleep. These devices deliver the same air pressure level throughout the night, which your sleep specialist determines through a sleep study or titration process.

Standard CPAP machines offer several advantages for sleep apnea patients. They’re typically the most affordable option among positive airway pressure devices and have the widest selection of models and features available. CPAP therapy is typically the first line of treatment for OSA, making these machines the starting point for most newly diagnosed patients.

Key features of standard CPAP machines include:

Fixed pressure delivery as prescribed by your doctor
Pressure relief settings on some models to reduce exhalation pressure slightly
Ramp-up features that gradually increase pressure as you fall asleep
Built-in humidifiers to prevent dryness and irritation
Data tracking capabilities to monitor therapy compliance

Auto-adjusting CPAP (APAP) machines

APAP is not a premium upgrade so much as a different titration strategy. AASM strongly recommends initiating PAP with either auto-adjusting PAP at home or an in-laboratory titration for adults with obstructive sleep apnea and no significant comorbidities, and recommends either CPAP or APAP for ongoing treatment (source: AASM). In practice, APAP is common when a lab titration is impractical or when pressure needs vary with position, weight or alcohol.

Auto-adjusting positive airway pressure (APAP) machines, also called auto-CPAP devices, represent a more sophisticated approach to sleep apnea treatment. Auto-adjusting positive airway pressure (APAP) machines, also referred to as auto-CPAP, can raise or lower the pressure based on your breathing patterns.

Unlike standard CPAP machines that deliver constant pressure, APAP devices continuously monitor your breathing and automatically adjust the pressure throughout the night. When you get an APAP machine, the doctor will likely have set an upper and lower limit of air pressure, but software on the device automatically adjusts air pressure within those limits.

APAP machines work particularly well for certain types of sleep apnea patients. This is often more comfortable for sleepers whose pressure needs change between sleep positions, or those who have trouble tolerating CPAP therapy. They’re also beneficial for people who experience seasonal changes in their breathing patterns due to allergies or other factors.

The main advantages of APAP machines include:

Automatic pressure adjustments based on real-time breathing patterns
Greater comfort for position-sensitive sleepers
Potential for lower average pressures throughout the night
Advanced algorithms that respond to breathing events automatically

Bilevel positive airway pressure (BiPAP) machines

Bilevel is a targeted tool rather than a general upgrade: AASM suggests that CPAP or APAP be used rather than bilevel PAP for the routine treatment of obstructive sleep apnea in adults (source: AASM). Bilevel comes into its own where a single high pressure is hard to exhale against, or where ventilation itself needs support.

Bilevel positive airway pressure machines, commonly known as BiPAP or BPAP devices, provide a more specialized form of treatment. Bilevel positive airway pressure (BiPAP or BPAP) machines have two pressure settings, switching between a higher pressure as you inhale and a lower pressure as you exhale.

This dual-pressure approach makes BiPAP machines particularly helpful for patients who struggle with standard CPAP therapy. A bi-level positive airway pressure (BiPAP) machine delivers different pressure, depending on whether you’re inhaling or exhaling. This type of machine might work for you if you need high pressure on inhalation and find CPAP therapy uncomfortable for exhalation.

BiPAP machines are typically prescribed for patients with specific conditions or circumstances:

Those who cannot tolerate the constant pressure of CPAP machines
Patients requiring high therapeutic pressures
People with certain respiratory conditions that cause carbon dioxide retention
Individuals with chronic progressive neuromuscular disorders

BiPAP machines often have a wider pressure range, reaching up to 30 cm H2O, making them suitable for more severe cases of sleep apnea or complex breathing disorders.

Travel and portable CPAP machines

For frequent travelers or those seeking more compact options, travel CPAP machines offer a convenient solution. The ResMed AirMini is our recommendation for the best portable CPAP machine in 2026. Compact in size, it’s a good option for overnight flights (FAA approved), camping, and other situations when it wouldn’t be practical to bring a full-sized CPAP machine.

Travel CPAP machines prioritize portability and convenience while maintaining effective therapy. These devices are significantly smaller and lighter than standard machines, making them ideal for business trips, vacations, and other travel situations. Many travel CPAP machines are FAA-approved for airline travel and can operate on battery power.

However, travel machines do have limitations. Portable machines are not designed for everyday use and can’t replace a full-size machine in terms of features, durability, or therapy quality. Most travel CPAP machines lack built-in humidifiers, though some offer waterless humidification options through special filters.

Important considerations for travel CPAP machines:

Significantly smaller and lighter than standard devices
Battery operation capabilities for camping or power outages
FAA approval for airline travel
Limited features compared to full-size machines
Generally not covered by insurance
Best used for short-term travel rather than nightly use

Specialized PAP machines

Beyond the main categories of CPAP machines, several specialized positive airway pressure devices serve specific medical needs.

Adaptive servo-ventilation (ASV) machines represent the most advanced form of PAP therapy. Adaptive servo-ventilation (ASV): ASV is for people with certain types of central sleep apnea. ASV monitors your breathing and adjusts the pressures to make your breathing more stable. It may also deliver a breath when necessary. These devices are typically prescribed for complex sleep apnea or central sleep apnea conditions.

Auto-bilevel PAP machines combine the benefits of BiPAP therapy with automatic pressure adjustments. Auto-bilevel PAP: This machine self-regulates the inhalation and exhalation pressures, providing both the dual-pressure approach of BiPAP and the adaptive capabilities of APAP technology.

Key features to consider when choosing a CPAP machine

Modern CPAP machines offer numerous features designed to improve comfort and therapy effectiveness. Understanding these features can help you select the device that best meets your needs.

Humidification systems help prevent common side effects like dry mouth, nasal congestion, and throat irritation. An integrated climate control humidifier helps reduce dryness and irritation. Most newer machines include built-in heated humidifiers with adjustable settings.

Data tracking and connectivity allow you and your healthcare provider to monitor therapy progress. The auto-adjusting pressure technology continuously adapts to your breathing patterns for optimal comfort. Its large, intuitive touchscreen interface simplifies operation. Many machines now offer smartphone app integration for easy data access and therapy insights.

Pressure ramp features help ease the transition to sleep by starting with lower pressure and gradually increasing to your prescribed level. The Luna G3 also has popular comfort features like an adjustable ramp setting which can gradually increase therapy pressure to your prescribed pressure over up an hour to help you fall asleep more comfortably.

Noise levels vary significantly between machines and models. This model operates quietly — around 26 decibels, roughly the sound level of a whisper in a quiet room. Quieter operation improves sleep quality for both users and their bed partners.

Benefits of CPAP therapy

The gains do not depend on which type you use. NHLBI lists better sleep quality and reduced snoring immediately, then help managing high blood pressure, lower stroke risk and improved cognitive function over time (source: NHLBI). AASM gives a strong recommendation for PAP over no therapy in adults with excessive sleepiness, and a conditional one for impaired sleep-related quality of life and comorbid hypertension (source: AASM). See our guide to CPAP benefits and how soon they appear.

Using the right type of CPAP machine consistently provides both immediate and long-term health benefits. You may notice immediate improvements after starting CPAP treatment, such as better sleep quality, reduction or elimination of snoring, and less daytime sleepiness.

Short-term benefits of CPAP therapy include:

Improved sleep quality and feeling more rested
Elimination or significant reduction of snoring
Decreased daytime fatigue and sleepiness
Enhanced mood and cognitive function
Better concentration and memory

Long-term health benefits of consistent CPAP use may include:

Improved blood pressure
Reduced risk of cardiovascular disease events, like heart attack and stroke
Improved memory and thinking abilities (cognitive function)
Lower risk of accidents due to improved alertness
Better management of related conditions like diabetes

Studies have found that people who treat OSA with a CPAP are less likely to be involved in a car crash or to have near-miss situations that result from drowsy driving, highlighting the safety benefits of effective treatment.

Insurance coverage and costs

Those thresholds are read off your sleep study report — our guide to reading your AHI result explains which index yours uses and why that matters.

Medicare sets the pattern most private plans follow: an in-person clinical evaluation before the sleep test, then an AHI of 15 or more, or 5–14 with documented excessive daytime sleepiness, impaired cognition, mood disorders, insomnia, hypertension, ischaemic heart disease or a stroke history. Continued coverage requires “use of PAP ≥4 hours per night on 70% of nights during a consecutive thirty (30) day period” within the first three months, plus a re-evaluation no sooner than day 31 and no later than day 91 (source: CMS).

Most insurance plans, including Medicare, provide coverage for CPAP machines when prescribed by a healthcare provider following a sleep study diagnosis. If you’re enrolled in Medicare Part B and you’ve been diagnosed with sleep apnea, Medicare may pay 80 percent of the cost for your CPAP machine, as long as the doctor who prescribes it is an approved Medicare provider.

Without insurance coverage, breathing machines can cost between $500 and $3,000, depending on whether you’re purchasing a CPAP, APAP, or BiPAP device. The variation in cost depends on the type of machine, features included, and manufacturer.

Many insurance providers require a rental period before you own the machine, and coverage terms vary significantly between plans. It’s important to verify your specific coverage details with your insurance provider and understand any requirements for compliance monitoring or regular follow-up appointments.

Choosing the right CPAP machine type

Note that the type is a clinical decision documented on your prescription, not a shopping preference — and in the US the machine is a prescription device either way. See how to get a CPAP prescription and our buying guide for prices and retailers.

Selecting the appropriate CPAP machine depends on several factors specific to your condition and lifestyle. CPAP machines are the simplest, most affordable, and most widely available option for sleepers experiencing OSA symptoms. If you are on a budget or looking for the biggest selection of models and features, a traditional CPAP machine may be the best choice.

Your sleep specialist will consider factors such as:

Severity of your sleep apnea
Required therapeutic pressure levels
Sleeping positions and movement patterns
Tolerance to continuous pressure
Budget and insurance coverage
Travel frequency and lifestyle needs

APAP machines are useful for those who have trouble sleeping with the constant pressure of a CPAP machine. They can also be effective for sleepers who experience regular changes in their breathing patterns, like allergy sufferers or those who change sleep positions frequently.

For those who cannot tolerate standard CPAP therapy, BiPAP machines provide a more specialized form of PAP therapy. A doctor usually only prescribes BiPAP treatment for people with OSA if they do not respond to traditional CPAP therapy.

Getting started with your CPAP machine

Expect support, and ask for it if it is not offered. AASM strongly recommends that educational interventions be given with the initiation of PAP therapy, and suggests behavioural and troubleshooting interventions plus telemonitoring-guided support during the initial period (source: AASM). That first month matters: around half of patients stop using PAP consistently after it (source: NIH – StatPearls).

Starting CPAP therapy successfully requires patience and proper setup. The first few nights on CPAP may be challenging as patients adjust to the therapy. Many initially find the mask uncomfortable, claustrophobic, or embarrassing.

To improve your adjustment to CPAP therapy:

Work with your healthcare provider to ensure proper mask fit and machine settings
Start by wearing the mask for short periods while awake to get accustomed to it
Use the ramp feature to gradually increase pressure as you fall asleep
Maintain consistent use every night, including during naps
Keep your equipment clean and replace parts according to manufacturer recommendations

Most people notice the benefits of CPAP therapy within the first two weeks. Some even notice a difference after the very first night of sleeping with their CPAP, but even if you don’t immediately notice the benefits, you should stick with your therapy for as long as possible.

Understanding the different types of CPAP machines available empowers you to work effectively with your healthcare provider to find the best solution for your sleep apnea treatment.

Whether you need a standard CPAP machine, an auto-adjusting APAP device, or a specialized BiPAP machine, the right choice can dramatically improve your sleep quality and overall health.

Frequently asked questions about types of CPAP machines

What are the main types of CPAP machines?

Three: fixed-pressure CPAP, which delivers one prescribed pressure all night; APAP, which adjusts automatically within a prescribed range; and BiPAP, which uses a higher pressure to inhale and a lower one to exhale. Travel machines are miniaturised versions of the first two.

Is APAP better than CPAP?

Not inherently. The American Academy of Sleep Medicine recommends that clinicians use either CPAP or APAP for the ongoing treatment of obstructive sleep apnea in adults. APAP is often chosen when an in-lab titration is impractical or when pressure needs vary with sleep position, weight or alcohol.

Who needs a BiPAP machine instead of CPAP?

AASM suggests CPAP or APAP rather than bilevel PAP for the routine treatment of obstructive sleep apnea. Bilevel is generally reserved for people who cannot exhale comfortably against a high single pressure, or who have conditions such as obesity hypoventilation or central sleep apnea.

What pressure range do CPAP machines cover?

Auto-adjusting units for adults typically operate between 5 and 15 cm H2O. An in-lab titration commonly starts at 5 cm H2O and steps up in 2 cm H2O increments until breathing events are controlled.

Do all types of CPAP machine need a prescription?

In the United States, yes. Every positive airway pressure machine, including travel units, is a prescription device. The type and pressure are specified on the prescription that follows your sleep study.

Planning a trip? See travelling with a CPAP machine for TSA, battery and altitude rules.

Sources

National Heart, Lung, and Blood Institute (NHLBI) – CPAP — definition, components and benefits
NHLBI – Sleep Apnea: Treatment — CPAP, BPAP and APAP as the three PAP types
NIH / NCBI StatPearls – Continuous Positive Airway Pressure — pressure ranges and titration
NIH / NCBI StatPearls – Obstructive Sleep Apnea — AHI severity thresholds and adherence
American Academy of Sleep Medicine – PAP therapy clinical practice guideline — CPAP vs APAP vs bilevel recommendations
Centers for Medicare & Medicaid Services – LCD L33718 — coverage criteria and adherence definition

How we source this guide

This guide is researched and written by the CPAP Community editorial team. We are writers and researchers, not clinicians. Clinical statements are traced to primary sources — the National Heart, Lung, and Blood Institute, the U.S. Food and Drug Administration, the Centers for Medicare & Medicaid Services and the American Academy of Sleep Medicine — and cited in the text so you can check them. We sell no CPAP equipment and take no manufacturer sponsorship. Nothing here is medical advice; see our medical disclaimer and speak to your own sleep clinician before changing your therapy.

Last reviewed by the CPAP Community editorial team: August 2026.

Types of CPAP machines: CPAP vs APAP vs BiPAP compared