Fitbit Sense 2 Advanced Health & Fitness Tracker Smartwatch
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td{font-size:.58rem;padding:4px 1px}.hrm-compare .th-model .th-lvl{display:none}} Skip to content Fitbit Sense 2 Advanced Health & Fitness Smartwatch The Sense 2 is Fitbit's most advanced smartwatch — built for users who want comprehensive health monitoring beyond basic fitness tracking. 1.58″ color AMOLED touchscreen (336 × 336 px) with always-on display option. Built-in GPS for phone-free pace and distance. Optical heart rate sensor with 24/7 monitoring. ECG app for atrial fibrillation detection. Continuous EDA sensor (cEDA) for all-day passive stress tracking. SpO2 blood oxygen monitoring. Skin temperature variation tracking. Gyroscope. On-wrist Bluetooth calling via built-in speaker and microphone. Amazon Alexa voice assistant. Google Maps turn-by-turn directions. Google Wallet (NFC) contactless payments. YouTube Music controls. 40+ exercise modes with real-time stats. Active Zone Minutes, Daily Readiness Score, Sleep Score, Cardio Fitness (VO2 Max). 5 ATM water resistance (50 m). Up to 6-day battery life. Fast charge: 12 min = 1 day of use. Bluetooth 5.0, Wi-Fi, NFC. Aluminum case with physical side button. Weight: ~1.3 oz (37.6 g) with infinity band. S & L infinity bands included. MPN: FB521BKGB-US (Shadow Grey/Graphite). UPC: 810073611429. MSRP: $299.95. [{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://www.heartratemonitorsusa.com/"},{"@type":"ListItem","position":2,"name":"Fitbit Smartwatches","item":"https://www.heartratemonitorsusa.com/collections/fitbit"},{"@type":"ListItem","position":3,"name":"Fitbit Sense 2 Smartwatch","item":"https://www.heartratemonitorsusa.com/products/fitbit-sense-2-smartwatch"}]},{"@context":"https://schema.org","@type":"Product","name":"Fitbit Sense 2 Advanced Health & Fitness Smartwatch","brand":{"@type":"Brand","name":"Fitbit"},"mpn":"FB521BKGB-US","gtin13":"0810073611429","sku":"FB521BKGB-US","url":"https://www.heartratemonitorsusa.com/products/fitbit-sense-2-smartwatch","offers":{"@type":"Offer","url":"https://www.heartratemonitorsusa.com/products/fitbit-sense-2-smartwatch","priceCurrency":"USD","price":"299.95","availability":"https://schema.org/InStock","seller":{"@type":"Organization","name":"Heart Rate Monitors USA"},"shippingDetails":{"@type":"OfferShippingDetails","shippingRate":{"@type":"MonetaryAmount","value":"0","currency":"USD"},"shippingDestination":{"@type":"DefinedRegion","addressCountry":"US"}}}},{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"Is the Fitbit Sense 2 better than the Fitbit Charge 6?","acceptedAnswer":{"@type":"Answer","text":"The Sense 2 ($299.95) adds continuous EDA stress tracking (cEDA), a gyroscope, on-wrist phone calling, Amazon Alexa, and a large 1.58-inch display. The Charge 6 ($159.95) counters with more accurate ML-enhanced heart rate, gym equipment HR streaming (Sense 2 lacks this), a longer 7-day battery, and nearly half the price. Both share ECG, SpO2, skin temp, GPS, NFC, and Google apps. For the most complete health picture with stress monitoring and a smartwatch, choose the Sense 2. For the best fitness tracking value, the Charge 6 wins."}},{"@type":"Question","name":"Is the Fitbit Sense 2 better than the Fitbit Versa 4?","acceptedAnswer":{"@type":"Answer","text":"The Sense 2 adds ECG, continuous EDA stress tracking (cEDA), skin temperature, and a gyroscope over the Versa 4. Both share the same 1.58-inch display, on-wrist calling, Alexa, GPS, NFC, Google apps, and 40+ exercise modes. The Sense 2 costs $70 more ($299.95 vs $229.95). If you want ECG and continuous stress monitoring, the Sense 2 is worth the premium. Otherwise, the Versa 4 delivers the same smartwatch experience for less."}},{"@type":"Question","name":"Does the Sense 2 have ECG?","acceptedAnswer":{"@type":"Answer","text":"Yes. The ECG app assesses your heart rhythm for atrial fibrillation (AFib). Hold your fingers on the corners of the watch for 30 seconds. Results are stored in the Fitbit app and can be shared with your doctor. Only the Sense 2 and Charge 6 have ECG in the current Fitbit lineup."}},{"@type":"Question","name":"What is continuous EDA (cEDA) stress tracking?","acceptedAnswer":{"@type":"Answer","text":"The cEDA sensor passively monitors electrodermal activity (tiny changes in sweat gland activity) throughout the day to detect signs of stress. When it detects elevated stress, you get a notification to reflect on your emotional state and take action. The Charge 6 has spot EDA (manual scans only). The Inspire 3 and Versa 4 have no EDA at all. The Sense 2 is the only Fitbit with continuous stress tracking."}},{"@type":"Question","name":"Can you take phone calls on the Sense 2?","acceptedAnswer":{"@type":"Answer","text":"Yes. Built-in speaker and microphone for Bluetooth calls from your wrist when your phone is nearby. Shared with the Versa 4. The Charge 6 and Inspire 3 cannot make calls."}},{"@type":"Question","name":"How long does the Sense 2 battery last?","acceptedAnswer":{"@type":"Answer","text":"Up to 6 days with typical use. Fast charge gives a full day in 12 minutes. Up to 12 hours with continuous GPS. Always-on display and cEDA reduce battery life. Inspire 3 lasts 10 days, Charge 6 lasts 7 days, Versa 4 also lasts 6 days."}},{"@type":"Question","name":"Does the Sense 2 have gym equipment HR streaming?","acceptedAnswer":{"@type":"Answer","text":"No. Gym equipment heart rate streaming is exclusive to the Fitbit Charge 6. The Sense 2 cannot broadcast heart rate to Peloton, NordicTrack, or Tonal machines."}},{"@type":"Question","name":"Does the Sense 2 require Fitbit Premium?","acceptedAnswer":{"@type":"Answer","text":"Core features work without Premium — ECG, cEDA, heart rate, GPS, exercise tracking, sleep stages, calling, Alexa, and Google apps. Premium ($9.99/month) unlocks Daily Readiness Score, Sleep Profile, advanced analytics, and guided workouts. Includes 6 months free."}}]}] Our Take: The Sense 2 is the top of the Fitbit lineup — the smartwatch for people who want every health sensor Fitbit can pack into a device. Its standout feature is the continuous EDA (cEDA) sensor that passively monitors your body's stress response throughout the day and nudges you when it detects elevated stress levels. Combined with ECG for heart rhythm checks, SpO2, skin temperature, a gyroscope, and all the standard heart rate and fitness metrics, the Sense 2 offers the deepest health picture of any Fitbit. On the smartwatch side, you get the same 1.58″ AMOLED display, on-wrist calling, Alexa, Google Wallet, Google Maps, and YouTube Music as the Versa 4. The trade-off: at $299.95, it's the most expensive Fitbit, nearly double the Charge 6 at $159.95, and it still lacks the Charge 6's ML-enhanced heart rate accuracy and gym equipment streaming. Battery life is 6 days — tied with the Versa 4 and shorter than the Charge 6 (7) or Inspire 3 (10). If understanding and managing stress is a priority, or if you want ECG plus a full smartwatch experience, the Sense 2 is the only Fitbit that does it all. If you don't need continuous stress tracking and can live without on-wrist calling, the Charge 6 delivers more fitness-focused value at nearly half the price. Why you'd choose this smartwatch Continuous EDA Stress Tracking (cEDA)The only Fitbit with all-day passive stress monitoring. The cEDA sensor detects electrodermal activity changes and sends notifications when your body shows signs of stress so you can log your mood and respond. The Charge 6 has spot (manual) EDA only; the Inspire 3 and Versa 4 have none. ECG for Heart Rhythm MonitoringECG app assesses your heart rhythm for atrial fibrillation (AFib). Hold your fingers on the watch corners for 30 seconds. Share results with your doctor. Only the Sense 2 and Charge 6 have ECG in the Fitbit lineup. Skin Temperature & Full Sensor SuiteTracks overnight skin temperature variation to spot trends related to illness, cycle, or recovery. Plus SpO2, gyroscope, irregular rhythm alerts, HRV, and breathing rate — the most complete sensor array in any Fitbit. 1.58″ AMOLED & On-Wrist CallingLarge, bright 336 × 336 px color display. Built-in speaker and mic for Bluetooth phone calls from your wrist. Always-on display option. Same screen and calling as the Versa 4. Alexa & Google Apps Built InAmazon Alexa for voice commands. Google Wallet for NFC tap-to-pay. Google Maps for turn-by-turn directions. YouTube Music controls. Quick replies to messages (Android). Built-in GPS & 40+ Exercise ModesTrack pace, distance, and route phone-free. 40+ exercise modes with real-time stats. SmartTrack auto-detects workouts. Active Zone Minutes, Daily Readiness Score, Cardio Fitness Score. 6-Day Battery & 5 ATM Swim-ProofUp to 6 days on a charge with typical use. Fast charge: 12 minutes gives a full day's use. Water resistant to 50 meters for pool, shower, and rain. Most Advanced Fitbit — Every SensorThe only Fitbit that combines ECG + continuous EDA + skin temp + SpO2 + gyroscope + GPS + calling + Alexa + NFC in one device. If you want everything, this is it. Tip: Tab to a reason and press Enter to expand the explanation. Press Escape to close. Who this smartwatch is perfect for Stress-conscious users who want passive, all-day EDA stress monitoring with automatic body-response notifications. Health-focused individuals who want every sensor Fitbit offers — ECG, cEDA, skin temp, SpO2, gyroscope — on one device. Smartwatch users who want a large display, phone calls, Alexa, and Google apps alongside comprehensive health tracking. Anyone managing a health condition who values ECG readings and detailed wellness data to share with their doctor. People who want the most feature-complete Fitbit available, regardless of price. Consider these alternatives if… You want the best fitness-tracking value with ECG, GPS, and gym HR streaming for nearly half the price → Fitbit Charge 6 at $159.95 You want the same smartwatch features without ECG/cEDA/skin temp and save $70 → Fitbit Versa 4 at $229.95 You want the cheapest Fitbit for basic steps, sleep, and heart rate → Fitbit Inspire 3 at $99.95 Feature highlights Health sensors & stress tracking ECG app for atrial fibrillation (AFib) detection Continuous EDA sensor (cEDA) — all-day passive stress monitoring Optical heart rate sensor (24/7 continuous) SpO2 blood oxygen monitoring (overnight) Skin temperature variation tracking Gyroscope Irregular heart rhythm notifications High/low heart rate alerts, HRV, breathing rate Stress Management Score with body-response notifications Smart features & calling On-wrist Bluetooth phone calls (built-in speaker + microphone) Amazon Alexa voice assistant Google Maps turn-by-turn directions Google Wallet (NFC contactless payments) YouTube Music controls Call, text, and app notifications Quick replies to messages (Android only) Timer, stopwatch, alarms, Find My Phone Customizable clock faces Fitness & activity tracking Built-in GPS 40+ exercise modes (run, cycle, swim, HIIT, weights, yoga…) SmartTrack auto-detection of workouts Active Zone Minutes, Daily Readiness Score (Premium) Cardio Fitness Score (VO2 Max estimate) Workout intensity map (GPS + HR zones) 24/7 steps, distance, calories burned, floors climbed No gym equipment HR streaming (see Charge 6) Hardware & battery 1.58″ color AMOLED touchscreen (336 × 336 px) Always-on display option Aluminum case with Gorilla Glass 3 Physical side button Up to 6-day battery life (varies with use; cEDA may reduce) Fast charge: 12 min = 1 day; up to 12 hrs continuous GPS 5 ATM water resistance (50 m) Bluetooth 5.0, Wi-Fi, NFC Weight: ~1.3 oz (37.6 g) with band Dimensions: 40.5 × 40.5 × 11.2 mm Bands: S (5.1″–6.9″) and L (6.2″–8.2″) infinity bands included What's in the box Fitbit Sense 2 smartwatch Small infinity band (S) and large infinity band (L) Charging cable 6-month Fitbit Premium trial (new/returning users) Specifications Specification Value Display 1.58″ color AMOLED touchscreen (336 × 336 px) Always-on display Yes Heart rate sensor Multi-path optical (24/7 continuous) ECG Yes (atrial fibrillation detection) EDA / Stress sensor Continuous EDA (cEDA) — all-day passive stress tracking SpO2 Yes (overnight blood oxygen monitoring) Skin temperature Yes (variation tracking) Gyroscope Yes GPS Built-in GPS NFC Yes (Google Wallet contactless payments) Wi-Fi Yes Speaker / Microphone Yes (on-wrist Bluetooth calling) Voice assistant Amazon Alexa Exercise modes 40+ Gym equipment streaming No (see Charge 6) Battery life Up to 6 days (varies; cEDA may reduce) Fast charge 12 min = 1 day; full charge ~2 hours Water resistance 5 ATM (50 m) Connectivity Bluetooth 5.0, Wi-Fi, NFC Sensors Multi-path optical HR, ECG, cEDA, SpO2, skin temp, gyroscope, accelerometer, altimeter, ambient light, vibration motor Weight (with band) ~1.3 oz (37.6 g) Dimensions 40.5 × 40.5 × 11.2 mm Band sizes S: 5.1″–6.9″ / L: 6.2″–8.2″ (both included) Compatibility iOS 16.4+ / Android 9+ Colors Shadow Grey/Graphite, Lunar White/Platinum, Blue Mist/Soft Gold MPN FB521BKGB-US (Shadow Grey/Graphite) UPC 810073611429 (Shadow Grey/Graphite) MSRP $299.95 USD Sense 2 vs Inspire 3 vs Charge 6 vs Versa 4 — Full Comparison Four Fitbit devices across three tiers. The Sense 2 is Fitbit's most advanced smartwatch with the most complete health sensor array. Focus or hover a row label for a plain-English definition. Inspire 3 — Entry Charge 6 — Best Value Sense 2 — Premium — You Are Here Loading image… ★ Premium — You Are HereFitbit Sense 2 $299.95 USD Shop Sense 2 → Loading image… Entry TrackerFitbit Inspire 3 $99.95 USD Shop Inspire 3 → Loading image… Best ValueFitbit Charge 6 $159.95 USD Shop Charge 6 → Loading image… SmartwatchFitbit Versa 4 $229.95 USD Shop Versa 4 → Health Sensors & Heart Rate Feature Sense 2★ You Are Here Inspire 3Entry Charge 6Best Value Versa 4Smartwatch Heart rate sensor?Optical sensor uses LED light to measure blood flow through the wrist. ML-enhanced means machine learning improves accuracy during fast movement. Optical Optical Optical (ML-enhanced) Optical ECG app?Electrocardiogram — checks your heart rhythm for atrial fibrillation (AFib). ✓Yes ✕No ✓Yes ✕No EDA / Stress sensor?Electrodermal activity sensor measures sweat gland changes. Spot = manual. Continuous (cEDA) = all-day passive. Continuous cEDA ✕No Spot EDA ✕No SpO2?Blood oxygen saturation monitoring. Tracks overnight. ✓Yes ✓Yes ✓Yes ✓Yes Skin temperature?Tracks overnight skin temperature variation. ✓Yes ✓Yes ✓Yes ✕No Irregular rhythm alerts?Automatic notifications for patterns consistent with AFib. ✓Yes ✓Yes ✓Yes ✓Yes Gym HR streaming?Sends heart rate to gym equipment — Peloton, NordicTrack, Tonal. ✕No ✕No ✓Yes ✕No Fitness, GPS & Smart Features Feature Sense 2★ You Are Here Inspire 3Entry Charge 6Best Value Versa 4Smartwatch Built-in GPS?Tracks pace, distance, route without your phone. ✓Yes Phone GPS only GPS + GLONASS ✓Yes Exercise modes?Number of sport/activity types tracked. 40+ 20+ (40+ via update) 40+ 40+ Google Wallet (NFC)?Tap to pay at any contactless terminal. ✓Yes ✕No ✓Yes ✓Yes Google Maps?Turn-by-turn directions on your wrist. ✓Yes ✕No ✓Yes ✓Yes YouTube Music?Control playback on your wrist. ✓Yes ✕No ✓Yes ✓Yes On-wrist calling?Phone calls via built-in speaker and mic. ✓Yes ✕No ✕No ✓Yes Voice assistant?Hands-free voice control. Alexa ✕No ✕No Alexa Notifications Calls, texts, apps Calls, texts, apps Calls, texts, apps Calls, texts, apps Display, Battery & Hardware Feature Sense 2★ You Are Here Inspire 3Entry Charge 6Best Value Versa 4Smartwatch Form factor?Band = slim tracker. Smartwatch = larger watch-style. Smartwatch Fitness band Fitness band Smartwatch Display?AMOLED = bright, vibrant colors with deep blacks. 1.58″ AMOLED 0.81″ AMOLED 1.04″ AMOLED 1.58″ AMOLED Display resolution 336 × 336 px Color Color 336 × 336 px Battery life?Maximum battery with typical use. Up to 6 days Up to 10 days Up to 7 days Up to 6 days Fast charge 12 min = 1 day ✕No ✕No 12 min = 1 day Water resistance?5 ATM = safe for swimming and showering. 5 ATM (50 m) 5 ATM (50 m) 5 ATM (50 m) 5 ATM (50 m) Weight?Weight with default band. ~1.3 oz (37.6 g) ~0.7 oz (20 g) 1.1 oz (31 g) ~1.3 oz (37 g) Physical button Physical side button ✕No Haptic side button Physical side button Speaker / Mic ✓Yes ✕No ✕No ✓Yes Wi-Fi ✓Yes ✕No ✕No ✕No MSRP?Manufacturer's suggested retail price in USD. $299.95 $99.95 $159.95 $229.95 Data based on official Fitbit/Google specifications. All four products are available at Heart Rate Monitors USA. Prices are MSRP and subject to change. If you notice an error, please contact us. CA Residents: Prop 65 Warning We work hard to keep product information accurate. If you spot an error, email us at [email protected] — we appreciate it. Fitbit Sense 2 — Frequently Asked Questions Is the Sense 2 better than the Charge 6?The Sense 2 ($299.95) adds continuous EDA stress tracking (cEDA), a gyroscope, on-wrist phone calling, Amazon Alexa, and a large 1.58″ display. The Charge 6 ($159.95) counters with more accurate ML-enhanced heart rate, gym equipment HR streaming (Sense 2 lacks this), a longer 7-day battery, and nearly half the price. Both share ECG, SpO2, skin temp, GPS, NFC, and Google apps. For the most complete health picture with stress monitoring and a smartwatch, choose the Sense 2. For the best fitness tracking value, the Charge 6 wins. Is the Sense 2 better than the Versa 4?The Sense 2 adds ECG, continuous EDA stress tracking (cEDA), skin temperature tracking, a gyroscope, and Wi-Fi over the Versa 4 ($229.95). Both share the same 1.58″ display, on-wrist calling, Alexa, GPS, NFC, Google apps, and 40+ exercise modes. If ECG and continuous stress monitoring matter to you, the Sense 2 is worth the extra $70. If you don't need those sensors, save the money with the Versa 4. Does the Sense 2 have ECG?Yes. The ECG app assesses your heart rhythm for atrial fibrillation (AFib). Hold your fingers on the corners of the watch for 30 seconds. Results are stored in the Fitbit app and can be shared with your doctor. Only the Sense 2 and Charge 6 have ECG in the current Fitbit lineup — the Inspire 3 and Versa 4 do not. What is continuous EDA (cEDA) stress tracking?The cEDA sensor passively monitors electrodermal activity — tiny changes in sweat gland activity — throughout the day to detect signs of stress. When it detects elevated stress, you get a notification to reflect on your emotional state and take action. The Charge 6 has spot EDA (manual scans only). The Inspire 3 and Versa 4 have no EDA at all. The Sense 2 is the only Fitbit with continuous, passive stress tracking. Can you take phone calls on the Sense 2?Yes. Built-in speaker and microphone for Bluetooth calls from your wrist when your phone is nearby. Shared with the Versa 4. The Charge 6 and Inspire 3 cannot make on-wrist calls. How long does the Sense 2 battery last?Up to 6 days with typical use. Fast charge gives a full day in 12 minutes. Up to 12 hours with continuous GPS. Always-on display and cEDA sensor may reduce battery life. For comparison: Inspire 3 lasts 10 days, Charge 6 lasts 7 days, Versa 4 also lasts 6 days. Does the Sense 2 have gym equipment HR streaming?No. Gym equipment heart rate streaming (Peloton, NordicTrack, Tonal, etc.) is exclusive to the Fitbit Charge 6. The Sense 2 cannot broadcast heart rate to exercise machines. Does the Sense 2 require Fitbit Premium?Core features work without Premium — ECG, cEDA stress tracking, heart rate, GPS, exercise modes, sleep stages, calling, Alexa, and Google apps. Premium ($9.99/month or $79.99/year) unlocks Daily Readiness Score, Sleep Profile, advanced analytics, guided workouts, and wellness reports. Includes 6 months free for new and returning users. Need help choosing? Call us at 1-800-403-8285 or 215-259-2700. Our team is happy to help you find the right fitness tracker. 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