Nike Sports Bra Size Guide
Convert your calculator measurements into Nike Alpha, Swoosh, and Indy fits, plan impact-specific support, and download the official conversion table for quick reference.
How to measure for Nike Alpha & Swoosh fits
Follow these calculator-backed steps before choosing your Nike size. Nike’s official chart (linked below) uses even band numbers and cup differences to map into alpha sizes from XS through 3X.
Set your calculator baseline
Run the Bra Size Calculator with a non-padded bra and note band, bust, and recommended sister sizes. Nike chart conversions assume this baseline.
Capture rib (band) measurement
Wrap the tape directly under the bust, exhale, and record to the nearest half-inch/cm. Round to the even band Nike uses (30, 32, 34, etc.).
Capture bust fullness
Measure around the fullest point while keeping the tape level. Subtract band from bust to identify cup difference (A–G).
Match to Nike Alpha size
Use the conversion table or download to map band + cup to Alpha (XS–3X) or Swoosh/Indy alpha sizes. Note impact preferences in the planner.
Log adjustments after testing
Perform a 10-jump test, jog-in-place, and overhead reach. Record strap column, hook choice, and sweat management in the downloadable planner.
Source: Nike Pro Bra sizing chart (PDF)
Conversion quick reference
Run the calculator first, then use the snapshot to jump from band/cup to Nike Alpha sizing. Print the PNG or keep it on your phone when you head to the fitting room.
Save the conversion snapshot
The downloadable CSV lists full mappings through 44 bands and cup ranges A–G so you can check edge cases or in-between alpha sizes.
| Bra size (US) | Nike alpha size | Recommended impact | Notes |
|---|---|---|---|
| 30C | Alpha XS | Light–Medium | Alpha compression keeps 30 bands anchored without over-tightening; switch to Swoosh pullover for barre days. |
| 30DD | Alpha Small | Medium–High | Tighten adjustable straps and cross the back for sprint intervals or HIIT ladders. |
| 32B | Alpha XS | Light–Medium | Works for studio work; size up to Small if you prefer looser compression for recovery classes. |
| 32DD | Alpha Medium | High | Match with Alpha or FE/NOM Flyknit for bounce control; lock racerback hook before tempo runs. |
| 34C | Alpha Medium | Medium–High | Use removable pads for shape on strength days; swap to Swoosh Medium for choreography rehearsals. |
| 34DD | Alpha Large | High | Pair with Nike Rival or Alpha high support; log hook column in the impact planner for repeat fits. |
| 36B | Alpha Medium | Medium | Keep straps parallel for bracing under the bar; convert to cross-back for plyometric finishers. |
| 36DD | Alpha XL | High | Use Alpha or Ultrabreathe high-support styles with molded cups for road races or jump-heavy circuits. |
| 38C | Alpha Large | Medium–High | Add bra liner for hot-weather runs; Indy High-Support in Large suits hybrid cardio days. |
| 38F | Alpha 2X | High | Look for adjustable clasp backs (Alpha High Support) and log strap settings between workouts. |
| 40D | Alpha 2X | Medium–High | Split between Alpha (max control) and Alate Luxe (softer compression) depending on Sports Advisor preset. |
| 42DD | Alpha 3X | Medium–High | Use extender-friendly backs and double-check band recovery in the senior comfort tracker if caregiving. |
Impact presets for Nike support levels
Log your training blocks in the impact planner, then match them to Nike collections with the visual map. Keep a copy handy so you know when to reach for Alpha High Support versus Indy Light days.
Download impact map
High support – running & HIIT
Alpha High Support, FE/NOM Flyknit, and Rival styles combine encapsulation + compression. Use racerback clips and firm bands for bounce control.
Match with
Sprints, tempo runs, plyometric circuits, bootcamp classes.
Medium support – studio & strength
Swoosh Medium Support and Indy UltraBreathe balance movement with structure. Adjust straps to parallel for lifting days.
Match with
Strength training, dance cardio, cycling, reformer Pilates.
Light support – recovery & lounge
Indy Light, Alate Minimalist, and Dri-FIT Indy provide stretch-focused comfort. Ideal when calculator suggests loosening to sister size.
Match with
Yoga, barre, mobility flows, travel and lounge days.
Style-by-style fit notes
Alpha High Support
Focus: Maximum impact with adjustable back clasp and molded cups.
Fit tip: Lock the back clasp on the second hook for races; use removable pads only if you need extra shape.
Swoosh Medium Support
Focus: Pullover compression layers with classic Nike swoosh styling.
Fit tip: If you sit between sizes, start with the larger alpha size, then tighten straps for choreography work.
Indy Light & Ultrabreathe
Focus: Strappy silhouettes that keep stretch and airflow for low-impact days.
Fit tip: Log strap crossings in the planner so you can reset them after washing.
FE/NOM Flyknit
Focus: Engineered knit encapsulation that molds to the body without seams.
Fit tip: Use the impact planner to note which knit zones deliver the best chest compression for your mileage blocks.
Lookbook: rotate styles by training block
Review the lookbook before you pack your gym bag so Alpha stays reserved for race day, Swoosh handles studio classes, and Indy supports active recovery. Tick off the bra you wore in the impact planner to keep elastic rotation balanced.
Download lookbook snapshot
Training-specific adjustments
Keep your calculator results in sync with real workouts. Adjust alpha sizes, strap tension, and panel settings based on how you move each week.
Runners & plyometric athletes
Start with Alpha High Support or FE/NOM Flyknit in the conversion table size. Cross the straps, set panel tension to match the Sports Advisor high-impact preset, and recheck after 3–4 miles.
Running bra checklistStrength & interval lifters
Rotate between Alpha Medium/High Support and Swoosh Medium for accessory days. Log hook column and strap placement in the strength-training support log so bench presses and sled pushes stay stable.
Strength support presetsYoga, barre & mobility crews
Indy Light and Alate Luxe alpha sizes favor stretch. Size via the calculator, then loosen to the sister band on recovery days so the elastic rebounds.
Yoga & low-impact roadmapTroubleshooting Nike fits
Band rides up mid-workout
Drop to the tighter sister band, switch to Alpha styles with clasp backs, and follow our band-riding-up diagnostics.
See detailed fixesStraps dig or slip
Convert to racerback, balance strap sliders, or clip in the hidden hook. Cushion straps for long runs after reviewing the strap-digging guide.
See detailed fixesCompression flattens or gaps
For flattening, loosen to the next alpha size and pair with molded cups; for gaping, tighten sliders and test FE/NOM Flyknit encapsulation.
See detailed fixesCare & replacement schedule
- Rinse immediately after sweaty sessions, then machine wash cold in a mesh bag with mild detergent—skip fabric softeners to protect Dri-FIT fibres.
- Air-dry on a flat rack or hang by the band so straps do not stretch. Alternate between at least three Nike bras to let elastic rebound within 24 hours.
- Audit fit every 6–9 months or after drastic training changes. Replace when the band stretches more than two inches or the cups lose recovery.
Downloadable training tools
Start each session with the impact checklist, then update the conversion CSV and planners so your calculator baseline stays aligned with real training data.
Nike alpha conversion table (CSV)
Full XS–3X mapping sourced from Nike’s official chart.
Nike conversion snapshot (PNG)
Keep the quick-reference table handy when shopping or packing gym bags.
Nike impact training checklist (PDF)
Log strap, panel, and recovery notes for each workout before updating the impact planner.
Impact level visual map (PNG)
Visualise Nike collections by support level before choosing your bra.
Workout impact planner (PDF)
Log panel settings, strap positions, and sweat notes for each training block.
Strength-day support log (CSV)
Track hook columns and recovery cues when alternating Nike bras for lifting days.
Nike lookbook snapshot (PNG)
Share the Alpha, Swoosh, and Indy rotation plan with teammates or clients.
Nike sports bra resources
Nike sports bra FAQs
Do Nike sports bras run small compared with everyday bras?
Nike Alpha sizes hug closer than typical everyday bras to manage bounce. Start with the conversion table, then test sister sizes: if the band rides up, drop one band size and increase the cup; if breathing feels restricted, move to the looser sister band.
Which Nike styles suit fuller busts or plus sizes?
Alpha High Support (XS–3X) and FE/NOM Flyknit offer clasp backs, molded cups, and reinforced straps. For 42DD and above, combine the Alpha 3X size with cross-back straps and log recovery days to let elastic rebound.
How can I stop straps from sliding during runs?
Convert to racerback, tighten sliders symmetrically, and perform a 10-jump test. Note the exact slider position in the impact planner so you can reset it after washing.
What if I sit between two Nike alpha sizes?
Choose the larger alpha size for everyday comfort, then tighten straps or use the Sports Advisor high-impact preset for hard workouts. The downloadable table flags “between sizes” notes so you know when to try both Small and Medium, for example.
Nike® is a registered trademark of Nike, Inc. This independent guide references official Nike sizing resources to help you translate calculator measurements into brand-specific fits.