How to Use CPAP Clarity: A Complete Guide

From SD Card to Insights in 60 Seconds

Your CPAP machine collects detailed data every single night, including pressure levels, leak rates, respiratory events and breathing patterns. Your machine's screen shows a single AHI number. The myAir app gives you a score and, on Air11 machines, a timeline of the night. Neither one shows you the full picture. (If you've been using OSCAR, CPAP Clarity gives you a similar depth of data with a simpler interface. Curious how every browser and desktop option stacks up? See best CPAP data tools compared for a feature matrix.)

CPAP Clarity does. It reads your raw SD card data and turns it into clear, actionable insights, all in your browser, all for free, with your health data never leaving your device.

CPAP Clarity supports ResMed AirSense 10, AirSense 11, AirCurve 10 (AutoSet, CPAP, VAuto, ASV, ST), the AirCurve 11 ASV and AirCurve 11 VAuto, the ResMed AirMini (usage only), AirStart 10 (nightly summaries) and older S9, the BMC E-20A and G3 A20, the React Health Luna G3, the Löwenstein Prisma Smart and prisma20A, the Philips DreamStation, DreamStation 2 and System One 60 Series, the Yuwell YH-450, YH-680/690, YH-725 and YH-920, and the Sefam S.Box AUTO. Here's how to get started.

What You Need

Three things to get started:

1. Your CPAP's SD card. Most machines come with one pre-installed and recording data every night, but not all. Some ResMed AirSense 11 units ship with a "dummy" training card that doesn't actually record, and refurbished or loaner machines may arrive without a card at all. If yours isn't recording, ask your supplier for a card that records, or see our SD card buyer's guide for which card to buy and how to format a fresh one.
2. A way to connect the card to your computer. Most laptops have a built-in SD slot. If yours doesn't, a USB card reader is inexpensive.
3. A computer, an Android phone with Chrome 132 or later, or an iPhone or iPad on iOS 18.4 or later. CPAP Clarity runs entirely in your browser.

Don't have your SD card handy? You can try CPAP Clarity with sample data right now. The demo loads a realistic session so you can explore the dashboard, insights, and reports before importing your own data.

Step 1: Find Your SD Card

Your ResMed machine stores therapy data on a standard SD card. You'll need to remove it briefly to import your data.

ResMed AirSense 11: Look on the left side of the machine for a small hinged door. Open it and gently push the SD card inward. It'll click and spring out slightly. Pull it the rest of the way with your fingers.

AirSense 10: The SD card slot is on the left side behind a small cover, opposite the humidifier water tub. Same push-to-eject mechanism.

AirCurve 10: The slot is on the left side, behind a small cover, opposite the humidifier (the same place as the AirSense 10). Same push-to-eject mechanism.

Don't worry about removing the card. Your machine continues recording to its internal memory while the SD card is out. Just remember to put it back when you're done so the next night's data gets saved to the card. For a complete walkthrough of what files are on the card and how to handle it, see our CPAP SD card guide. For phone-based import, see How to Import CPAP Data on Your Phone.

Not sure which SD card or reader works with your machine? Our SD card buyer's guide covers card types, sizes, and reader recommendations. If your card isn't working, see our SD card troubleshooting guide.

Step 2: Import Your Data

Open cpapclarity.com in your browser. You'll see the import area front and center.

Option A: Drag and drop. Open your SD card in your file browser and drag the whole SD card onto the import area on the page. This gives CPAP Clarity both your therapy data (in the DATALOG folder) and your machine settings (model, mode, pressure, EPR), so you get the most complete analysis.

Option B: Choose your SD card. Click "Choose your SD card" in the import area and go to your SD card. Select the SD card's root folder and confirm. If your SD card folder lives on Google Drive, iCloud, OneDrive, or Dropbox, see importing CPAP data from cloud storage first; cloud placeholder files can cause a confusing "no sessions found" error before the import even runs.

Option C: Oximeter or wearable file. If what you have is one file from an app rather than an SD card (a pulse oximeter's CSV or .spo2 file, an Oura export, an Apple Health export.zip, a Fitbit, Garmin or Samsung export), click "Oximeter or wearable file" instead. The SD card button opens a folder picker, and a folder picker shows single files grayed out, so it can't pick one. On a device page such as Oxygen, the Import Data button opens the file picker for you. If your export is an unzipped folder, drag the folder onto the import area.

CPAP Clarity will read your files and process the data. This usually takes just a few seconds, even for months of recorded sessions.

Importing again later. Your imported nights stay saved in this browser until you clear them, so importing the same machine's card again never starts you over. Each time, CPAP Clarity reads the whole card, refreshes the nights on it, adds the new ones, and keeps the older nights it already saved, even ones your card no longer holds, so your history keeps building. (Importing a different machine's card replaces the earlier machine's nights, and the site asks you first.) In Chrome on a computer you can skip the picking: press "Remember my CPAP folder for next time" once, and after that "Check for new nights" reads the same folder again whenever you press it.

About your privacy: All processing happens entirely in your browser using JavaScript. Your CPAP data is never uploaded to any server. There's no account to create, no cloud sync, no data collection. Your health information stays on your device. Period. Learn more about our privacy approach in CPAP Data Privacy.

Step 3: Read Your Night

Once your data loads, you'll see your most recent night. Here's what you're looking at, from the top down:

The night's date. The date heads the page, with arrows to step to an older or newer night and a calendar button to jump to any night. Switches below it turn each source you've imported (your CPAP, an oximeter, a wearable) on or off.

The headline. The big number is the night's count of breathing events (a machine that saves only a daily summary gives its rate an hour instead, and one that records only usage, such as the AirMini, shows your hours on the mask). The line under it gives the rate, your Apnea-Hypopnea Index in events an hour, and notes that under 5 is the mark the AASM associates with well-controlled therapy. Next to it (below it on a phone), a short sentence each covers your hours on the mask, the events by type (obstructive, central, hypopnea), your mask leak and, when you've added an oximeter, your oxygen.

Your night, hour by hour. A ribbon draws the whole night on one clock, with your pressure and leak as lanes (your breathing rate too on a night with no oximeter or wearable, and your oxygen when you've added an oximeter) and each scored event as a dot, lettered O for obstructive, C for central and H for hypopnea. Below it, event tiles give each event's time and type. Tap a tile to see that moment on the ribbon.

Tonight against your usual. Three bars set the night's events an hour, hours on the mask and mask leak against your own usual range from your recent nights. Published marks are drawn where they fall, such as the under-5 mark the AASM associates with well-controlled therapy and Medicare's 4-hour line.

What your data means. One list says what the night's data shows in plain English. Things to Watch come first, then a short narrative paragraph, then the night's other readings. More on this list in Step 4.

More from the night. Small panels show your pressure across the night and, when you've imported them, your oxygen and pulse from an oximeter and your sleep stages from a wearable.

For your doctor. When the night raised questions worth asking, they're listed here in plain words, next to the buttons for the report and Copy for AI.

Every chart and number. This drawer, closed until you open it, holds the rest. Detailed Charts put every signal on one clock with a crosshair you can pin, so you can line events up with leak spikes or pressure changes. The night's numbers give pressure, leak and flow limitation across the night, then the events by type. Your machine shows the settings from your last import (model, therapy mode, pressure range, EPR, mask type, humidity) and the parts you replace. See Central vs Obstructive Apnea for what the event types mean.

Step 4: Understand What Your Data Means

The "What your data means" list is where CPAP Clarity translates your numbers into plain English.

Instead of wondering what a leak rate of 28 L/min means, you'll see something like "High leak rate", telling you your typical leak was at or above 24 L/min, the line ResMed sets for its mask seal, and that your mask may not be the right size or type. Visit our leak fix guide for practical solutions.

If your events are primarily central apneas rather than obstructive, you'll see "Mostly central events", explaining that these are labeled as central (brain-signaling pauses, not airway collapse) and that the treatment approach may differ.

The things that matter most appear first. Short sessions under 2 hours are recognized as naps and won't trigger false compliance warnings.

Step 5: Browse Your History

Click History in the navigation bar to see your therapy over time. This is where patterns emerge that single-night views can't reveal.

The centerpiece is your Therapy Score, a number from 0 to 100 that combines four parts of your data:

Component	Points	What It Measures
AHI	35	Breathing events per hour across the nights scored
Usage	25	Average hours of use per night, with full credit at 7 or more
Mask Seal	20	Your average leak, where your machine's leak can be scored
Consistency	20	The share of days that reached 4 hours of use

The score always looks at your most recent 14 nights of therapy (naps left out), and it is worked out the same way every time. That means on the same machine, one two-week score lines up with the next. It appears from your third night, so at first it covers fewer nights. History shows how the score moved against the 14 nights before it, and which part has the most points left to gain. After you switch machines it shows no change, because the change would measure the switch. The score sums up your data. It is not a verdict on your treatment, so bring a change you notice to your doctor, who can say what it means for you.

Trend Charts show your AHI, leak rate, and usage plotted over time. You can pick the last 7, 30 or 90 days, all of your nights, the nights since your last doctor's visit, or a custom range. Look for patterns: is your AHI creeping up? Did a mask change reduce your leak rate?

Compare Periods. Pick a date (like when you changed masks or adjusted pressure) and see your before-and-after averages side by side. This makes it easy to measure the impact of changes to your therapy.

Step 6: Download Your Report

CPAP Clarity generates a comprehensive PDF report you can save, print, or share with your doctor. From either the dashboard or history page, click "Download Full Report". An options panel lets you choose the period the report covers (last 30, 60, or 90 nights, all of your data, or a custom date range) and optionally add your name, date of birth, and a short note for your doctor. Those details are stored only on your device and appear only in the PDF you export.

The report includes your AHI breakdown by event type, key metrics with ratings, time-series charts, and a plain-English narrative summary. It's formatted for clinical review so your sleep physician can quickly scan and act on the data. Learn more about what to bring to your sleep doctor visit.

Step 7: Export for AI Analysis

Want deeper analysis? Click "Copy all nights for AI" on the dashboard or history page to copy your therapy data to the clipboard in a structured, plain-text format. Paste it into ChatGPT, Claude, or any AI assistant and ask questions like "what changed in my therapy after I got the new mask?" or "why has my AHI trended up over the last month?". The export includes nightly AHI, usage, leak, pressure, event counts, machine settings, and any manual nights you've marked, but it never leaves your device until you choose to paste it somewhere.

Size cap: the export is capped at the most recent 365 nights (roughly one year) to stay under typical clipboard and AI message limits. If you have more than a year of stored nights, the button label changes to "Copy last year for AI" and the oldest nights past the cap are left out of the paste. Your full history stays intact in the browser; only the copied snapshot is trimmed.

For the full walkthrough, including what stays private and how to decide what to share, see pasting your CPAP data into ChatGPT or Claude.

Step 8: Back Up and Manage Your Data

Click Backup in the navigation bar (on a phone, open the menu first). Everything that isn't part of your nightly review lives here.

Back up your data. Because CPAP Clarity keeps everything in your browser, clearing your browser storage, switching computers, or having iOS evict the site can all wipe your history. The Back up your data card lets you download a single .zip file containing every session, event, and machine setting. Save it to iCloud Drive, Google Drive, or an external hard drive. Restore it later on any computer or browser with one click. Nothing uploads to our servers.

Mark manual nights. Used a travel CPAP or forgot your SD card? Click Mark manual nights and pick the dates. Your consistency score stays accurate instead of breaking a streak on a night you actually slept on CPAP.

Storage usage. A small panel shows how much browser storage CPAP Clarity is using and whether any sessions are eligible for automatic cleanup. Sessions less than 90 days old are always protected.

Advanced data controls (collapsed by default): delete individual sessions, remove everything older than 90 days, or clear all data. Every destructive action asks for confirmation first, and your SD card is never touched.

Try It Now, No SD Card Needed

Not ready to import your own data? No problem. On the homepage, click "Open the sample night" to load a realistic demo session. You'll see exactly how the dashboard, insights, and reports work, so when you're ready to plug in your SD card, you'll know exactly what to expect.

Common Questions

What if I don't have an SD card reader? Most laptops have a built-in SD card slot on the side or front edge. If yours doesn't, a USB card reader is inexpensive and plugs into any USB port. See our SD card buyer's guide for specific recommendations.

Can I use CPAP Clarity on my phone? On Android, yes, in Chrome 132 or later. Connect your SD card to your phone using a USB-C card reader, then open CPAP Clarity in Chrome and import normally. On iPhone and iPad with iOS 18.4 or later, Safari supports the same folder upload flow via a USB-C or Lightning SD card reader. Older versions can pick single files but not the whole card folder, so update first or use a computer. See our phone import guide for step-by-step instructions.

Do I need to import every night? No. Your SD card accumulates data automatically. Import whenever you want to check your data: weekly, monthly, or before a doctor's appointment. CPAP Clarity reads the entire card each time, refreshes the nights on it, and keeps the older nights already saved in your browser, even once your card has dropped them. For long-term archival (machine swap, card replacement, switching providers), our backup CPAP data guide covers a safe routine.

Can I compare Therapy Scores from different two-week periods? Yes, on the same machine. The score always covers your most recent 14 nights and is worked out the same way every time, so one two-week score lines up with the next. History shows how it moved against the 14 nights before, and shows no change after you switch machines. A change in the score is something to look into and bring to your doctor, not a verdict on its own.

What devices does CPAP Clarity support? ResMed AirSense 11, AirSense 10, AirCurve 10 (AutoSet, CPAP, VAuto, ASV, ST modes), the AirCurve 11 ASV (Adaptive Servo Ventilation) and AirCurve 11 VAuto, the ResMed AirMini (usage only), AirStart 10 (nightly summaries) and older S9, the BMC E-20A AutoCPAP, the BMC G3 A20 AutoCPAP, the React Health Luna G3, the Löwenstein Prisma Smart and prisma20A, the Philips DreamStation, DreamStation 2 and System One 60 Series, the Yuwell YH-450, YH-680/690, YH-725 and YH-920, and the Sefam S.Box AUTO, plus Wellue pulse oximeters and major wearables. If you have a different machine, send us a copy of its SD card so we can work on adding it.

A Few Things That Make This Smoother

CPAP Clarity itself is free and runs entirely in your browser. A handful of small accessories make the workflow noticeably less painful:

• A replacement SD card if yours is missing or worn out. Your supplier can send one, or the SD card buyer's guide covers which card to buy and how to format a fresh one.
• USB-C SD card reader for laptops without a built-in slot, or Lightning SD card reader for iPhone / iPad import on iOS 18.4 or later.
• Wellue O2Ring overnight oximeter if you want to layer overnight SpO2 readings on top of your CPAP data. The dashboard joins both streams automatically; see Pulse Oximeter for CPAP for setup.

Your Data, Your Control

CPAP Clarity exists because your therapy data belongs to you, and understanding it shouldn't require a medical degree or complex desktop software. Whether you're preparing for a doctor's appointment, tracking your progress, or just curious about what happens while you sleep, your data is waiting on that little SD card.

Pull it out. Drop it in. See what your CPAP has been recording.

Start analyzing your CPAP data →