Withings band size chart by model

Withings is the rare smartwatch maker that never left the width system. Every watch in the range has real lugs and ordinary quick release spring bars, so band sizing is a plain lug width in millimeters, not a proprietary connector or an S/M/L band class [1] [16] [23]. The whole catalog runs on exactly two widths: 18mm on every case of 39mm and under, and 20mm on every 42 to 43mm case [1] [2] [3] [4]. The traps are naming traps, not width traps: the ScanWatch Nova 42mm takes 20mm while the Nova Brilliant 39mm takes 18mm [5] [9], the Steel HR 36mm and 40mm sit one width apart [14], and the Pulse HR tracker is not a spring-bar watch at all [21] [22]. This chart carries the width, the official wrist range where Withings publishes one, and the mechanism, with two sources on every row.

Quick answers: ScanWatch 38mm and ScanWatch 2 38mm take 18mm. ScanWatch Light 37mm takes 18mm. ScanWatch Nova Brilliant 39mm takes 18mm. Steel HR 36mm takes 18mm. Move, Move ECG and Activite take 18mm. ScanWatch 42mm and ScanWatch 2 42mm take 20mm. ScanWatch Nova 42mm takes 20mm. ScanWatch Horizon 43mm takes 20mm. ScanWatch Vitals 38mm takes 18mm and the 42mm takes 20mm. Steel HR 40mm and Steel HR Sport take 20mm. All on quick release spring bars, so standard 18mm and 20mm bands fit. The Pulse HR is the exception and has its own refused-row disclosure below.

Two widths, one mechanism

The system is short enough to memorize. Every Withings watch case measuring 39mm or less takes an 18mm band: that is the ScanWatch 38mm and ScanWatch 2 38mm, the ScanWatch Light 37mm, the Nova Brilliant 39mm, the Steel HR 36mm, the Move, the Move ECG and the Activite generation [1] [6] [9] [16] [20]. Every 42 or 43mm case takes a 20mm band: the ScanWatch 42mm, ScanWatch 2 42mm, Nova 42mm, Horizon 43mm, Vitals 42mm and the Steel HR 40mm with the Steel HR Sport [1] [2] [4]. There is no 22mm, no odd width, no hidden third size anywhere in the current catalog. The mechanism is uniform too: Withings' own replacement instructions describe quick release spring bars with a pull-knob on every watch line from the Steel HR to the ScanWatch Vitals [1] [13] [14] [16], and the factory shop sells its leather, FKM and metal bands with stainless steel quick release spring bars in exactly 18mm and 20mm variants [3] [4] [27].

The chart: 15 verified rows

Every row below carries at least two independent surfaces: Withings' own support articles and user guides, the Withings accessories shop's per-band compatibility lists, the maker's press documentation, or independent reviews. Widths are the lug-end width in millimeters. Official wrist fit is quoted only where Withings itself publishes a range; a dash means no first-party figure exists.

Withings band width and official wrist fit by model
ModelCaseBand widthOfficial wrist fitNotes
ScanWatch 38mm38.4 mm18 mm146 to 211 mmthe base rule of the whole brand: 38mm model requires 18mm bands, quick release spring bars, FKM factory band [1] [2] [3]
ScanWatch 42mm42 mm20 mm163 to 239 mmthe 42mm sibling takes 20mm; the shop's 20mm band page lists this exact watch as compatible [1] [2] [4]
ScanWatch 2 38mm38.4 mm18 mm146 to 211 mmsame case and width as the original, 18mm FKM band stated in the dimensions article [5] [3]
ScanWatch 2 42mm42 mm20 mm163 to 239 mm20mm FKM band, 12.9mm thick case; shop compatibility lists match it to every 20mm band [5] [4]
ScanWatch Light 37mm36.8 mm18 mm146 to 211 mmthe slimmest ScanWatch at 9.85mm thick keeps the 18mm width; nominal 37mm case is 36.8mm measured [6] [3]
ScanWatch Nova 42mm42 mm20 mm163 to 239 mmthe luxury diver shares the ScanWatch 2 platform: 20mm at the lugs, factory oyster bracelet tapers 20 to 18mm [5] [7] [8]
ScanWatch Nova Brilliant 39mm39 mm18 mmnot publishedthe trap row: same Nova name, one step down in case, one width down in band; the factory 5-link bracelet and the shop compatibility lists are all 18mm [9] [3] [28]
ScanWatch Horizon 43mm43 mm20 mmFKM 165 to 240 mm, metal 140 to 220 mmthe biggest case in the range stays at 20mm; both factory bands published at 20mm with separate wrist ranges, metal link bracelet sold as a 20mm item for the 43mm case [2] [27] [4]
ScanWatch Vitals 38mm38.4 mm18 mm146 to 211 mmthe clinical line repeats the 38mm 18mm rule with an FKM band; wristband article says any band of the right width works [11] [12]
ScanWatch Vitals 42mm (Healthmaster)42 mm20 mm163 to 239 mmthe 42mm Vitals and the Healthmaster naming share the 20mm FKM band and the 163 to 239mm range, per the shared support section [11] [12] [13]
Steel HR 36mm36 mm18 mmnot published36mm exists only as the plain Steel HR; accepts any spring bar band 18mm wide and shares bands with Activite, Activite Pop and Withings Steel [14] [15]
Steel HR 40mm / Steel HR Sport40 mm20 mmnot publishedthe Sport only exists in 40mm; both take 20mm, and the shop lists the Steel HR 40mm among the 20mm-compatible watches [14] [15] [4]
Move / Timeless Chicvaries18 mmup to 215 mmone width for the whole analog line: any band 18mm wide fits, quick release spring bars, stated in the replacement article [16] [29]
Move ECG38 mm18 mmup to 200 mm18mm confirmed in two official texts: the French support article allows any band no wider than 18mm and the user manual requires 18mm bands; 14 to 20cm wrists [17] [18] [19]
Activite / Activite Popnot stated18 mmup to 215 mmthe original hybrid generation set the 18mm pattern: any 18mm band fits, and the Steel HR article confirms the same 18mm bands cross-fit the Steel and Steel HR 36mm [20] [15]

ScanWatch family: one split, four names

The ScanWatch line looks like four different products and is one sizing rule wearing four names. The original ScanWatch: 38mm case takes 18mm, 42mm takes 20mm, wrist ranges 146 to 211mm and 163 to 239mm, all published in Withings' own replacement and dimensions articles [1] [2]. The ScanWatch 2 repeats the identical split with the identical ranges, right down to the same 38.4mm measured case diameter [5]. The ScanWatch Light drops the ECG and the thickness, 9.85mm against 13.2mm, but keeps 18mm on its 36.8mm case [6]. The ScanWatch Vitals and Healthmaster, the FDA-cleared clinical versions, repeat the 38/42 split one more time, and their support articles state outright that you can use any wristband you like as long as it is the right width [11] [12]. If you know which of the two case sizes is on your wrist, you know the band; the model year does not matter.

Nova and Nova Brilliant: same name, different width

The Nova pair is the one place the Withings naming actively misleads. The ScanWatch Nova is a 42mm luxury diver on the ScanWatch 2 platform: 20mm bands at the lugs, a factory oyster bracelet that tapers from 20mm to 18mm, per Withings' own launch documentation, and a product page whose entire accessory list, metal link, curved leather, FKM, runs 20mm [5] [7] [8]. The Nova Brilliant sounds like a finish variant and is not: it is a 39mm case, and everything made for it is 18mm, from the factory Metal 5-Link bracelet to the shop's 18mm compatibility list that names the Brilliant alongside the ScanWatch 2 38mm and the Light [9] [3] [28]. An independent review of the Nova also confirms the mount is a standard 20mm quick-release lug with plentiful third-party options [25], which is the pattern for the whole chart. Buy Nova bands as 20mm and Brilliant bands as 18mm, and never assume the Nova label carries the width.

Horizon: the biggest case keeps 20mm

The ScanWatch Horizon is the diver-styled ScanWatch with a 43mm case, and it is the width ceiling of the brand: still 20mm. Withings' dimensions article publishes both factory options at 20mm with different wrist coverage, the FKM band fitting 165 to 240mm wrists and the metal bracelet 140 to 220mm [2], and the shop's Horizon metal link bracelet is sold by its exact name and width, 20mm, against the 43mm case [27]. The lesson for buyers with small wrists: the Horizon's fit range floor of 140mm on the metal bracelet is lower than the 42mm ScanWatch's 163mm floor, because bracelet link sizing, not the case, sets the minimum. Anyone shopping cross-model should still treat 20mm Horizon and 20mm ScanWatch bands as interchangeable in width, since the mount is the same quick release spring bar [1].

Steel HR and Steel HR Sport: the 36 versus 40 split

The Steel HR is the line where the two-width rule was first written down. Withings' replacement article states it flat: the 36mm model requires 18mm bands, the 40mm model requires 20mm bands, both on quick release spring bars [14]. The 36mm case exists only as the plain Steel HR; the Steel HR Sport exists only in 40mm, so the Sport is always a 20mm watch [14] [26]. The same FAQ adds the one cross-compatibility wrinkle in the brand: the 36mm Steel HR accepts any 18mm spring bar band and shares its bands with the Activite, Activite Pop and Withings Steel, while the 40mm model takes any 20mm spring bar band but does not swap with those older 18mm models [15]. That is the whole Steel HR sizing story: measure nothing, just read the case size off the dial.

Move, Move ECG and Activite: the 18mm flat

Below the Steel HR, everything Withings has ever put lugs on is 18mm. The Move and Timeless Chic replacement article says it in one sentence: the wristbands are 18mm wide, fit wrists up to 215mm, and you can use any wristband you like as long as it is 18mm [16]. The Move ECG, the stainless-electrode version, is confirmed by two official texts: Withings' French support article allows any strap no wider than 18mm, and the user manual requires 18mm bands on its 38mm case, with wrists to 200mm [17] [18] [19]. The Activite generation, the original 2014 hybrids, set the pattern with the same sentence Withings still uses: 18mm bands, wrists to 215mm, any 18mm band fits [20]. This flat zone is also why the Steel HR 36mm owner has a huge catalog: every Activite and Move band ever made fits their watch [15].

Quick release spring bars, and what they mean for third-party bands

Every Withings watch in the chart attaches its band with quick release spring bars: a spring bar with a pull-knob on the underside, released by hand with no tools. Withings says so in print for the ScanWatch [1], the ScanWatch Vitals [13], the Steel HR [14], the Move [16] and the Move ECG [18], and the shop's own band pages list stainless steel spring bars for quick release as a specification on every leather, FKM and metal band [3] [4]. That has a direct consequence the smartwatch buyer does not expect: ordinary third-party 18mm and 20mm bands fit. Withings itself licenses the idea in its support articles, any wristband you like as long as it is the right width [12] [15] [16] [20], strap retailers sell Withings-specific bands on the standard-spring-bar mount across the range [23] [24] [29], and the Nova review measured standard 20mm quick-release lugs [25]. A 20mm band bought for a Seiko 5 fits a ScanWatch 42mm. That sentence is the entire reason a width chart is sufficient for this brand, and the Pulse HR refusal below is the exception that proves it.

Official wrist ranges, and where Withings does not publish them

Withings is one of the few makers that publishes per-model wrist circumference ranges instead of leaving fit to band length charts. The two standard ranges: 146 to 211mm for every 38mm-class case and 163 to 239mm for every 42mm-class case, printed identically for the ScanWatch, ScanWatch 2, Light and Vitals [1] [5] [6] [11]. The Horizon is the one case-size exception, with separate FKM and metal ranges [2]. The older lines state ceilings instead of ranges: Move and Activite to 215mm, Move ECG to 200mm [16] [18] [20]. The Steel HR and Nova Brilliant have no published per-case range at all, so for those, and for any wrist near a boundary, measure your circumference first: the paper-strip measuring method takes a minute, and the shop band pages publish their own cuff ranges, 147 to 202mm on the 18mm curved leather and 160 to 226mm on the 20mm, which bracket the same answer from the band side [3] [4]. The smartwatch sizing guide covers how these ranges compare with Apple's and Samsung's.

Not a connector question

Do not confuse Withings band sizing with the connector systems that dominate smartwatches. Apple Watch bands slide into case slots and are keyed by case size, Pixel Watch bands click into a proprietary connector, and Galaxy Fit bands use a one-click mount with no lugs at all; on those, you shop by model, and a width number does not exist. Withings is the opposite: a hybrid watch with ordinary lugs, ordinary spring bars and a plain millimeter width, so a $12 standard 18mm band is a complete answer to the question "what fits my ScanWatch 38". The lug width chart places the brand's two-width catalog against every other brand's spread, and the watch band size chart is the hub for all of them. If you are coming from an Apple Watch, the one habit to unlearn is buying bands by model name: within Withings, the case size, not the product name, is the entire compatibility key, which is exactly how the Nova 42mm at 20mm and the Nova Brilliant 39mm at 18mm end up on different bands despite sharing a name.

What the strap shops cannot tell you

Third-party coverage of Withings sizing is broad but sliced thin. The dedicated guide that ranks best is a single-model page for the Steel HR only, correct on the 36mm 18mm and 40mm 20mm split but silent on every ScanWatch [26]. The strap retailers run one collection page per watch line, which works if you already know your model and simply relists the widths this chart anchors to the manufacturer [23] [24] [29]. Nobody assembles the whole brand on one page with the official wrist ranges next to the widths, because the shop compatibility lists that would do it are spread across every individual band product page [3] [4]. That fragmentation is the gap this chart fills, and the refusal section below is the part no shop page will ever print.

Rows we refused to publish

Two lines could not reach two agreeing surfaces and are excluded from the chart. The Pulse HR tracker: Withings confirms replacement wristbands exist and fit wrists from 140 to 200mm, but no first-party text states a band width, and the mount is not the spring-bar system the watches use; band owners report the tracker needs an adapter before a standard 12mm strap mounts at all [21] [22]. It is sized by its own replacement parts, not by a lug width, so no width row is honest. The original Pulse and the Go, the clip-and-wristband activity trackers: no width statement from any first-party surface, same non-standard mount class, same refusal. If you own one of these, the sizing answer is the Withings accessories page for your exact model, not any millimeter number on this or any other chart.

Your watch is not in the table

Work the case size, not the model name. If the dial reads 36 to 39mm, buy 18mm; if it reads 40 to 43mm, buy 20mm; those two sentences cover every Withings watch ever sold with lugs. If the model is not in the chart and does not obviously match either rule, check the case back or the product page for the diameter, and if even that fails, measure between the lug horns in millimeters as the measuring guide shows. The lug width chart gives the cross-brand context for 18mm and 20mm as standard widths, the smartwatch sizing guide explains the official wrist-range system, and the band size chart hub ties the brand set together. And if your Withings is a Pulse HR, reread the refusal above before buying anything.

Related guides

For the same treatment of other sport-watch lines, see the Garmin band size guide (QuickFit versus quick-release, the closest large-catalog cousin), the COROS band size chart, the Amazfit band size chart (the brand where connectors, not widths, decide everything, the exact opposite of Withings), the Fitbit band size chart, the Huawei band size chart (the other maker that publishes official wrist ranges per model), the Suunto band size chart, and the Polar band size chart (the Vantage V2 and Pacer Pro adapter rule). The general system all of these build on is in the watch band size chart and the lug width chart by brand; the spring bar sizes behind every quick-release mount are in spring bar sizes, swapping technique in the spring bar tool guide, and whether a 43mm Horizon suits your wrist at all is a separate question in case size by wrist and smartwatch sizing.

Sources

  1. Withings Support, ScanWatch - Changing the wristband of my watch: quick release spring bars; 38mm model requires 18mm bands, 42mm model 20mm; wrists 146-211mm (38) and 163-239mm (42): support.withings.com
  2. Withings Support, ScanWatch - What are the dimensions of the watch: 38.4mm case with 18mm FKM band, 42mm case with 20mm FKM band; Horizon 43mm with 20mm FKM (165-240mm) and 20mm metal (140-220mm): support.withings.com
  3. Withings shop, Curved Leather Wristband 18mm: compatibility list Nova Brilliant 39mm, ScanWatch 2 38mm, ScanWatch Light 37mm, ScanWatch 38mm; cuffs 147-202mm; stainless quick-release spring bars: withings.com
  4. Withings shop, Curved Leather Wristband 20mm: compatibility list ScanWatch Nova 42mm, ScanWatch 2 42mm, ScanWatch Horizon 43mm, ScanWatch 42mm, Steel HR 40mm; cuffs 160-226mm; stainless quick-release spring bars: withings.com
  5. Withings Support, ScanWatch 2 - Watch dimensions and materials: 38.4mm case 18mm FKM (146-211mm), 42mm case 20mm FKM (163-239mm), ScanWatch Nova 42mm 20mm FKM (163-239mm): support.withings.com
  6. Withings Support, ScanWatch Light - Watch dimensions: 36.8mm case, 9.85mm thick, 27.1g, 18mm FKM band, wrists 146-211mm: support.withings.com
  7. Withings press, ScanWatch Nova launch release: ships with an oyster bracelet that tapers from 20mm to 18mm: media.withings.com
  8. Withings, ScanWatch Nova 42mm Blue product page: Metal Full Link Nova 20mm bracelet included; every listed accessory band (leather, FKM, woven) 20mm: withings.com
  9. Withings shop, Metal 5-Link ScanWatch Nova Brilliant Wristband: 18mm, compatible with Nova Brilliant 39mm Silver and Gold: withings.com
  10. Withings shop, Milanese Wristband 18mm: compatibility list ScanWatch 2 38mm, ScanWatch Light 37mm, ScanWatch Nova Brilliant 39mm: withings.com
  11. Withings Support, ScanWatch Vitals / Healthmaster - Dimensions: Vitals 38mm (38.4mm case) with 18mm FKM band, Vitals 42mm with 20mm FKM band, ranges 146-211mm and 163-239mm: support.withings.com
  12. Withings Support, ScanWatch Vitals / Healthmaster - Wristband issues: use any wristband you like; 38mm model requires 18mm wide bands, 42mm model 20mm: support.withings.com
  13. Withings Support, ScanWatch 2 - Changing the wristband: silicone, leather, premium sport and woven PET bands attach on quick release spring bars; 38mm 18mm, 42mm 20mm: support.withings.com
  14. Withings Support, Steel HR / Steel HR Sport - Replacing the wristband of my watch: quick release spring bars; 36mm model (Steel HR only) requires 18mm bands, 40mm model (Steel HR and Sport) 20mm: support.withings.com
  15. Withings Support, Steel HR / Steel HR Sport - Can I change the wristband of my watch: 36mm replaced with any spring bar band 18mm wide, compatible with Activite, Activite Pop and Withings Steel bands; 40mm any spring bar band 20mm, not compatible with those: support.withings.com
  16. Withings Support, Move / Timeless Chic - Replacing the wristband: wristbands are 18mm wide, fit wrists up to 215mm, any 18mm band works, spring bar pull-knob procedure: support.withings.com
  17. Withings Support (FR), Move ECG - Puis-je changer le bracelet: any band of your choice as long as it is no wider than 18mm; wrists 14 to 20cm: support.withings.com
  18. Withings Support, Move ECG user guide: quick release spring bars; 38mm case, 13mm thick; wristband fits wrists up to 200mm: support.withings.com
  19. Move ECG official manual text (retailer-hosted copy): Move ECG requires wristbands that are 18mm wide: eirberg.is
  20. Withings Support, Activite / Pop - Replacing the wristband: wristbands are 18mm wide, fit wrists up to 215mm, use any wristband you like as long as it is 18mm: support.withings.com
  21. Withings Support, Pulse HR - Can I change the wristband of my watch: wristbands available on the website; fit wrists 140 to 200mm; no width published (refused row): support.withings.com
  22. r/withings, Pulse HR replacement straps thread: standard 12mm straps need an adapter to mount on the Pulse HR (refused row corroboration): reddit.com
  23. Nothing But Bands, Withings ScanWatch Light bands: 37mm case takes 18mm; standard spring bar rather than a proprietary connector, the same mechanism across the Withings range: nothingbutbands.com
  24. Nothing But Bands, Withings ScanWatch bands: 42mm ScanWatch, 42mm ScanWatch 2 and 43mm Horizon take 20mm; 38mm ScanWatch and ScanWatch 2 take 18mm: nothingbutbands.com
  25. WearableBeat, ScanWatch Nova review 2026: both included bands use standard 20mm quick-release lugs, so third-party options are plentiful: wearablebeat.com
  26. watchband.direct, Withings Steel HR bands guide (the incumbent single-model page): 36mm requires 18mm, 40mm and Sport 20mm; no other Withings model covered: watchband.direct
  27. Withings shop, ScanWatch Horizon Metal Link Wristband 20mm Silver: compatible with the 43mm ScanWatch Horizon; fits 138-220mm wrists: withings.com
  28. Withings, Compare watches page: ScanWatch Nova 42mm listed with 20mm wristbands, Nova Brilliant 39mm and ScanWatch Light 37mm with 18mm wristbands: withings.com
  29. Nothing But Bands, Withings watch bands collection: the 18mm size is used on every Withings case 39mm and under (ScanWatch 38, ScanWatch 2 38, Light, Nova Brilliant, Steel HR 36, Move): nothingbutbands.com