Free sleep and oximetry tools
No account, no email, no upload. Each tool runs in your browser and forgets everything when you close the tab.
- Live HRVMeasure heart rate variability from your oximeter's pulse waveConnect a Checkme O2 Max over Bluetooth and take a 1 to 5 minute reading. You see the live pulse wave, heart rate and RMSSD, and can download every beat interval.Needs: A Wellue Checkme O2 Max and Chrome or EdgeOpen
- Session viewerSee the charts and metrics for one night of oximeter dataLoad a night from a Wellue O2 device by CSV or Bluetooth. You get the same charts and metrics as the full app, and a one-page report you can print.Needs: A recording pulse oximeterOpen
- Sleep apnea risk checkSee whether your symptoms are worth raising with a doctorA one-minute checklist of published risk factors. You get a risk result in plain English and a next step.Needs: Nothing but a minuteOpen
- Compare nightsPut up to four recordings side by sideLoad two to four CSV exports and see them on one time axis, with every metric in one table. Try a night on your side against a night on your back.Needs: Two or more recordingsOpen
- Oximetry results explainerMake sense of the numbers on an overnight oximetry reportType in your ODI, lowest SpO2, average or time under 90%. Each number is placed against published reference ranges and explained in plain English.Needs: A report from any deviceOpen
- Altitude oxygen calculatorSee the blood oxygen range reported at a given elevationEnter an elevation or pick a town or trek. You get the air pressure and the SpO2 range reported for healthy visitors, and you can add your own reading to compare.Needs: An elevation, or a destinationOpen
- ODI and T90 calculatorWork out a desaturation index and time under 90% from your own countsEnter the number of desaturation events and the hours recorded to get an oxygen desaturation index, or the minutes under 90% to get T90. Each result is placed in a low, elevated or high band, with where the band comes from.Needs: Event count and recording lengthOpen
- Pulse oximeter accuracy calculatorSee the range a reading could really sit inEnter a reading and the accuracy figure your oximeter states, and see the range the true value is likely to fall in. Covers skin tone, perfusion, movement and nail polish, with the published research behind each.Needs: A reading and a stated accuracyOpen
- Oxygen level by agePublished SpO2 and sleeping heart rate ranges for each age bandA reference table of SpO2 and heart rate ranges from published studies, awake and asleep. Add your own reading to see whether it sits inside, below or above the range reported for your age.Needs: Your age, optionally a readingOpen
- Blood oxygen on a planeWhat cabin altitude does to an SpO2 reading in flightPick an aircraft type and a flight length to see the cabin altitude and the SpO2 range published studies report for it. Add a reading taken on board to see how it compares.Needs: An aircraft type and flight lengthOpen
- Oximeter data exportSave nights from an O2Ring or Checkme O2 without ViHealthConnect over Bluetooth, list the nights stored on the oximeter, and save each one as a CSV or as the raw device file that OSCAR can import. Nothing is uploaded.Needs: A Wellue oximeter and Chrome or EdgeOpen
- Oximeter file converterTurn Wellue, Contec, ChoiceMMed or any oximeter CSV into one formatDrop a raw Wellue file, a Contec CMS50 .SpO2 file, a ChoiceMMed MD300W1 .dat file or a CSV from any app, and save it as a ViHealth-format CSV the session viewer reads. Nothing is uploaded.Needs: An oximeter file or CSVOpen
- Overnight oximeter pickerCompare recording oximeters against what you needAnswer a few questions about form factor, overnight memory, vibration alert and Bluetooth, and get the devices ranked against your answers, with a spec table. No store links.Needs: A minuteOpen
- Sleep experiment plannerPlan a night-by-night test of one changePick something to test, such as sleep position, alcohol or a late dinner, and get a printable calendar of baseline nights and shuffled A and B nights, with what to keep the same and which numbers to compare.Needs: A change you want to testOpen
- Recording quality checkerSee how much of a night has usable readingsLoad a recording and see probe-off stretches, gaps in the file, movement and one-sample jumps on a timeline, with the longest gaps and their clock times. It looks at the data, not the values.Needs: A recording from a Wellue O2 deviceOpen
- Night-to-night variationSee how much your overnight numbers move from night to nightType in your ODI, T90, lowest or average SpO2 for 2 to 14 nights. You get the average, the spread, the running average, and roughly how many nights it takes for the average to settle.Needs: Numbers from 2 or more nightsOpen
Why these are free. PulseOxTracker sells one thing: keeping your nights so you can see the trend. The analysis is not the paid part.
Where to start
- Own a recording oximeter? Load a night in the session viewer.
- No device yet? The risk check takes a minute.
- Already have a report? The results explainer covers each number on it.
- Only have an event count? The ODI and T90 calculator turns it into a desaturation index.
- Want your nights off an O2Ring or Checkme O2 without ViHealth? Use the data export.
- Still choosing a device? The oximeter picker compares them.
Not a medical device. Does not diagnose, treat or prevent any condition. Discuss results and changes with a clinician.