| Fitbit Blaze | Fitbit Ionic | |
 |  | |
| Tech specs | ||
| Size | Width 40mm (Sizes depend on type of band) | Watch Width: 38mm Watch Thickness: 12mm |
| Material | Stainless steel clasp, Classic band (elastomer), Metal band (stainless steel metal), Leather band (soft, genuine leather) | - Strong & lightweight 6000 series aerospace-grade aluminum. - The wristband is made of a flexible, durable elastomer material |
| Charging | USB | USB |
| Battery | Lithium-polymer | Lithium-polymer |
| Battery life | up to 5 days | 4+ days with a GPS battery life up to 10 hours (1-2 hours charge time) |
| Water-resistance | Sweat, rain and splash proof. | up to 50 metres (swim-proof) - 5 ATM |
| Weight | 43 grams | 50 grams |
| Sensor | 3-axis accelerometer, 3-axis gyroscope, Optical heart rate monitor, Altimeter, Ambient light sensor and Vibration motor | Altimeter, 3-axis accelerometers, digital compass, GPS, optical heart rate monitor, ambient light sensor, pulse Ox, vibration motor. |
| Display | Touch-screen colour LCD. | Hi-res touchscreen (up to 1000 nits). Corning Gorilla Glass 3 display. |
| Screen size | 19.05mm x 25.4mm | 29 x 21mm, 348 by 250 pixels |
| Colors | Classic (Black, Blue and Plum), Leather (Black, Camel and Mist Gray), Metal | Comes is Sport, Leather and Classic versions. |
| Other | - Saves 7 days of detailed motion data – minute by minute. - Saves daily totals for past 30 days | |
| Activity tracking | ||
| Steps | Yes | Yes |
| Distance | Yes | Yes |
| Calories burned | Yes | Yes |
| Activity | Yes | Yes |
| Floors | Yes | Yes |
| Sleep | Yes | Yes (light, deep & REM) |
| Heart rate | 24/7 | Yes + HRV (premium subscription) |
| Stress & recovery | ||
| Pulse Ox | Yes | |
| Respiration rate | Yes (premium subscription) | |
| UV exposure | ||
| Skin temperature | Yes (premium subscription) | |
| Galvanic skin response | ||
| Hydration level | ||
| Calorie intake | ||
| GPS | Connected GPS | GPS/GLONASS |
| Running features | Pace, distance & routes | |
| Swimming features | Lap count, duration & calorie burn | |
| Other | Guided breathing, music control. | - Guided breathing sessions - Female health tracking |
| Non-fitness functions | ||
| Smartphone notifications | Yes | Call, text and calendar notifications |
| On-board music storage | Yes, 2.5GB (300 songs) + access Pandora | |
| Connected pay | Yes | |
| LTE | ||
| Links | ||
| Affiliate link* | Amazon | Fitbit | Amazon | Fitbit |
| Read more | Review | Review |
**All tech specs and images on this page come from manufacturers. These may change over time as manufacturers sometimes update their devices. While we cannot guarantee absolute accuracy of information on this page, we promise to review this content regularly and do our best to bring you the most up-to-date information. To be absolutely sure of tech specs of a particular device, we recommend checking the manufacturer’s website.