Is this a replacement for OSCAR or my doctor's software?

No. OSCAR is the free desktop program for in-depth CPAP analysis, and your clinic has its own tools. This page is for a quick look at a card or an EDF file on any computer without installing anything. It shows what the machine recorded and does not give medical advice.

What is the difference between "Machine AHI" and "Events per hour of use"?

Machine AHI is the number the machine itself stored in the card's daily summary (STR.edf). Events per hour of use is plain arithmetic done here: the apneas and hypopneas in the machine's event list for that night, divided by the hours of use. Arousals are listed but not counted. The two can differ slightly, for example through rounding. Neither is a diagnosis.

Which CPAP machines does it read?

It follows the published layout of ResMed AirSense 10 and AirSense 11 cards (and AirCurve 10, which writes the same files). Older S9 cards use different names in the daily summary, so some summary columns may be empty, but their EDF recordings still open. Philips, Fisher & Paykel and other makers write their own formats, which this page does not read.

Is my sleep data uploaded anywhere?

No. The files are read by your browser on your device. Nothing from the card is sent to this site or anyone else, and the card's serial number is not shown.

Stays on your computer How this works

Free CPAP data viewer for ResMed SD cards and EDF files

Open the SD card from a ResMed CPAP machine, or any EDF or EDF+ sleep recording, and see each night's flow, pressure, leak and recorded events on a chart - entirely in your browser

Drag & drop the SD card folder or .edf files here, or browse

ResMed AirSense / AirCurve cards · EDF · EDF+ · BDF · nothing is uploaded

Not a medical tool. This page shows what the machine or recorder wrote to the file. It does not diagnose anything or judge whether numbers are good or bad; talk to your doctor or sleep clinic about your therapy.

About this CPAP data viewer

CPAP machines record every night on their SD card: how long the mask was on, the air pressure, how much air leaked, the breathing flow itself and a list of the events the machine detected, such as apneas and hypopneas. ResMed machines write all of this as EDF files, the same European Data Format sleep labs and hospitals use for sleep studies (polysomnography), EEG and other body signals.

This page reads those files in your browser. Open the whole SD card folder to get a list of nights with the hours of use and the summary values the machine stored, then open a night to see its flow, pressure, leak, breathing rate and (with an oximeter) oxygen level and pulse on a chart, with the machine's events marked along it. Any other EDF or EDF+ recording opens too: a sleep study, a hypnogram, an EEG. Health data stays on your device: nothing is uploaded. It is free to use, with no account and no upload limit, and it runs entirely in your browser: nothing is uploaded, and while the page stays open, a feature you have already used keeps working offline.

What you can do

Open a ResMed SD card folder (AirSense 10 and 11 layout) and list the nights with hours of use, the machine's AHI, leak and mask pressure as recorded
See a night's flow and pressure (25 samples a second), leak, minute ventilation, snore, flow limitation and oximetry on a zoomable chart
See the machine's events - obstructive, central and unclassified apneas, hypopneas, arousals - marked on the chart and listed
Open any EDF, EDF+ (continuous or discontinuous) or BDF file, show or hide each signal, and read its annotations
Zoom from the whole night down to single breaths; large files are read a piece at a time, not loaded whole
Save the stretch on screen as CSV, the annotations as CSV, and the card's daily summary as CSV

How to open your CPAP SD card

Take the SD card out of the machine while it is not running therapy, and put it in your computer's card reader.
Press "Choose the SD card folder" and pick the card itself, or drag the card's folder onto the page. Your browser may ask to confirm that the page can read the folder.
Pick a night to see its charts. Put the card back in the machine afterwards; nothing on it is changed.

What this was tested with

The EDF reader was written for this site from the published EDF and EDF+ specifications and checked against public sleep-study recordings from the Sleep-EDF Expanded database on PhysioNet (Kemp et al., Open Data Commons Attribution licence), comparing signal values and annotations with the open-source pyEDFlib and edfio readers. The ResMed support was built from the card layout as publicly documented by the OSCAR project and other open-source readers, and tested on synthetic test cards made to that layout - no real ResMed card was available. If your card does not open, or a number looks wrong next to what the machine or OSCAR shows, please use "Report a problem" below the tool and say which machine it came from.

Questions

Is this a replacement for OSCAR or my doctor's software?: No. OSCAR is the free desktop program for in-depth CPAP analysis, and your clinic has its own tools. This page is for a quick look at a card or an EDF file on any computer without installing anything. It shows what the machine recorded and does not give medical advice.
What is the difference between "Machine AHI" and "Events per hour of use"?: Machine AHI is the number the machine itself stored in the card's daily summary (STR.edf). Events per hour of use is plain arithmetic done here: the apneas and hypopneas in the machine's event list for that night, divided by the hours of use. Arousals are listed but not counted. The two can differ slightly, for example through rounding. Neither is a diagnosis.
Which CPAP machines does it read?: It follows the published layout of ResMed AirSense 10 and AirSense 11 cards (and AirCurve 10, which writes the same files). Older S9 cards use different names in the daily summary, so some summary columns may be empty, but their EDF recordings still open. Philips, Fisher & Paykel and other makers write their own formats, which this page does not read.
Is my sleep data uploaded anywhere?: No. The files are read by your browser on your device. Nothing from the card is sent to this site or anyone else, and the card's serial number is not shown.

For DICOM medical images, use the DICOM Viewer; for heart rate and other data from a fitness watch, the FIT Viewer.