SleepyHead Is Gone — What to Use Now to Read Your SD Card

If you searched for SleepyHead and landed here, you're not alone — years after it stopped being updated, people still type "SleepyHead CPAP" into Google looking for a way to read their SD-card data. The short version: SleepyHead was discontinued back in 2019, but its work didn't vanish. It evolved into a successor that's still going strong, and there are now even simpler ways to see what your machine recorded overnight.

This guide walks through what happened, your real options for reading an SD card today, and how to switch tools without losing the history you've already built.

What happened to SleepyHead

SleepyHead was a free, open-source desktop program that let CPAP users open the data their machine wrote to its SD card and see it themselves — apnea events, leak rates, pressure, and detailed breathing waveforms — instead of relying on a manufacturer app that shows only a friendly summary.

It earned a loyal following because it answered a question manufacturer apps often dodge: what actually happened while I slept?

SleepyHead was discontinued in 2019. Active development stopped, and the original program is no longer maintained or recommended for new machines. That matters because:

• Newer CPAP models and firmware can change how data is written to the card, and an unmaintained program may not parse them correctly.
• You won't get bug fixes or support for newer devices.
• Download links you find floating around the web may be outdated or unsafe.

The good news is that discontinuation wasn't the end of the project — it was a handoff.

SleepyHead became OSCAR

The same community that built SleepyHead carried the work forward under a new name: OSCAR (the Open Source CPAP Analysis Reporter). OSCAR is the direct, actively maintained successor. If a forum, a Reddit thread, or an old blog tells you to "use SleepyHead," the modern equivalent is almost always OSCAR.

OSCAR kept what people loved about SleepyHead and added support for newer machines. It's a free desktop application that reads your SD card locally on your own computer. We cover it in depth in the OSCAR CPAP Software Guide, and if you want help interpreting the screens, see How to Read OSCAR Charts in Plain English.

A few practical things to know about OSCAR before you commit:

• It's free and runs on your own machine (Windows, macOS, Linux). Your data stays local.
• There's no auto-scoring. OSCAR shows you the numbers and charts; it doesn't interpret them or flag what's noteworthy for you. You do the reading.
• No Chromebook support. Because it's a desktop install, Chromebooks and most tablets are out.
• There's a learning curve. The detail is the point — but it can feel like a cockpit the first time you open it.

OSCAR is the right tool if you enjoy digging into raw data and don't mind installing software. But it isn't the only path anymore.

Reading your SD card today — the options

Reading your SD card means physically pulling the card from your machine (turn the machine off first), putting it in a card reader, and opening the data with software. Manufacturer apps like ResMed's myAir or what was Philips' DreamMapper sync over the internet instead — but they hide most of the detail.

Here's how the common routes compare:

A few notes that trip people up:

• myAir gives you a 0–100 score, not your data. The score leans heavily on usage hours and doesn't break out event types, leak detail, or flow limitation; the exact formula has never been published. You can score 100 with an AHI near 5. We unpack this in How to Read Your ResMed myAir Score (and What It Hides).
• DreamMapper shut down in January 2026, leaving Philips users looking for a new home for their data.
• The Philips DreamStation 2 writes encrypted SD-card data that OSCAR and most third-party tools cannot read. If you have a DS2, your tool choice is narrower — see Philips DreamStation 2: Why Its Data Is Encrypted and Your Options.

If you're brand new to pulling the card, start with How to Download CPAP Data from Your SD Card.

A simpler cloud route

SleepyHead became OSCAR — and SomniCharts is the even simpler cloud option. Instead of installing desktop software and learning to read raw charts yourself, you upload your SD card (or its folder) in a web browser and get a plain-language read of your night, no install required.

SomniCharts imports ResMed, Philips Respironics (including the encrypted DreamStation 2), and Löwenstein prisma data, then explains it automatically — what your AHI means, whether your leaks are in range, what your pressure settled at — in everyday English. Its built-in analysis (SomniDoc) does the interpreting that OSCAR leaves to you, which is the biggest difference between a desktop tool and a guided cloud one.

That said, no single tool reads every machine. If you want a side-by-side of who reads what, see OSCAR vs SleepHQ vs SomniCharts: Which Tool Reads Which Machine, and for the wider browser-based landscape, OSCAR Alternatives: Best Web-Based CPAP Analysis Tools.

Cloud route in three steps:

1. Pull the SD card from your (powered-off) machine and connect it to your computer or phone.
2. Upload the data folder through the browser — no software to install.
3. Read the plain-language summary of your AHI, leak rate, pressure, and events.

One thing every tool should do for you, and a reason cloud guidance helps: a large leak can invalidate your AHI. When air escapes faster than the machine expects, it can't reliably detect events, so your reported AHI may be artificially low. ResMed flags excess leak above 24 L/min at the 95th percentile (note that ResMed reports excess leak while Philips reports total leak — different baselines). A tool that surfaces this in plain language keeps you from trusting a "good" number that's really a leak artifact. More on that in CPAP Leak Rate: What's Acceptable and How to Fix High Leaks.

Switching without losing your history

The fear that keeps people on SleepyHead — or on a manufacturer app — is losing the trend they've built. Here's the reassuring part: your CPAP machine, not the software, owns your history. Most machines store roughly a year (sometimes more) of summary data on the SD card itself, with detailed waveforms for a shorter recent window.

That means switching tools doesn't erase your past:

• Use the same SD card. Whatever you load into OSCAR or a cloud tool reads from the card's existing files, so months of summary data come along for the ride.
• Don't reformat or wipe the card when switching. That's the one action that actually deletes history.
• You can run more than one tool. Loading your card into a new tool doesn't remove it from another — nothing stops you from keeping OSCAR for deep dives and a cloud tool for quick plain-language reads.

If you're also changing machines (say, ResMed to Philips, or onto a new device after the Philips recall), data continuity gets a little more involved because vendors store data differently. We cover that specific situation in Switching CPAP Brands? Keep Your Data History Across Vendors.

What the numbers actually mean once you can see them

Reading your data is only useful if you know what "good" looks like. A couple of anchors as you start interpreting:

• A residual AHI below 5 events per hour is the widely used benchmark for effective CPAP therapy — the AASM defines an "optimal" titration as fewer than 5 events per hour, which is also the normal (non-apneic) range. Some clinicians aim lower when it's comfortably achievable, but there's no formal guideline setting "below 1" or "below 2" as a standard, and goals are individualized with your provider. See What Is a Good AHI on CPAP?.
• Device-reported AHI isn't lab-scored AHI. Your machine estimates events from airflow and pressure; it has no EEG to detect arousals, so its number can differ from a sleep lab's. And remember: a single night is mostly noise — what matters is the trend over weeks. (Why Does My AHI Change Night to Night?)

If you spot rising central (clear-airway) events after you start reading your data, don't try to fix it by raising pressure yourself. CPAP reliably splints the airway open and treats obstructive events, but it doesn't directly correct the unstable breathing drive behind central apneas. A rise in central events can signal treatment-emergent central sleep apnea (TECSA), which often resolves on its own within weeks to a few months of continued CPAP — but persistent cases deserve a clinician's evaluation, not DIY pressure changes. We explain it in Central Apneas Showing Up on CPAP.

Quick FAQ

Is SleepyHead safe to download in 2026? It's no longer maintained, so it may misread newer machines and downloads from unofficial sites can be risky. Use OSCAR (its successor) or a cloud tool instead.

SleepyHead vs OSCAR — what's the difference? They're the same lineage. OSCAR is the actively maintained continuation of SleepyHead, with support for newer devices. There's no reason to choose discontinued SleepyHead over OSCAR.

Do I have to install software to read my SD card? No. OSCAR is a desktop install, but cloud tools like SomniCharts let you upload your card in a browser and get a plain-language read with nothing to install.

Will switching tools delete my old data? No — your history lives on the SD card and in your machine. As long as you don't reformat the card, your past data comes with you.

For the bigger picture on which tool fits your machine and your comfort level, start with our CPAP Data Tools & Apps hub.