How to open and convert your CSV file from Cardiogram

You’ll receive a CSV (comma-separated values) file when you export your heart rate data from Cardiogram. This file contains each heart rate (BPM) reading along with a timestamp for when it was recorded.

🕒 Understanding the timestamp format

Your timestamps follow the ISO 8601 format:

Example: 2020-11-22T01:00:00+01:00

Part	Example	What it means
Date	`2020-11-22`	Year-Month-Day (YYYY-MM-DD)
Time	`01:00:00`	24-hour clock (01:00 = 1 AM, 13:00 = 1 PM)
Time zone offset	`+01:00`	1 hour ahead of UTC (`-08:00` for California)

These timestamps let you match heart rate data to the exact time and time zone in which it was recorded.

🔍 Open or edit your CSV file

Google Sheets

→ Open Google Sheets

Free and browser-based
Supports sorting, filters, and timestamp formatting
Great for sharing or printing

ExtendsClass CSV Viewer

→ Use ExtendsClass

No login required
Easy for previewing, scrolling, and checking file content

🌐 Compare or convert timestamps

Time.is – Compare Time Zones

→ Go to Time.is

Manually enter timestamps
Compare local time across zones
Helpful for interpreting the +01:00 or -07:00 part of your data

🔄 Convert your CSV to other formats

ConvertCSV.com

→ Visit ConvertCSV

Convert to Excel, JSON, or SQL
Preview and filter rows before exporting
Ideal for developers or power users

💬 Still need help?

We're happy to walk you through your CSV file or help decode your data. Just email us at [email protected].