The answer — one pick, priced
Get the
Polar H9
$10 under your budget
The best accuracy-per-dollar strap — 2 top reviewers' value pick delivers nearly all the H10's clinical accuracy for $35 less, giving up only onboard memory and the second Bluetooth channel.
Fit ledger — need → measured evidence
■ The catch — co-equal billing, always
It's the stripped-down Polar. No onboard memory and a single Bluetooth channel — it records no untethered swim and pairs to one device at a time, a watch or a phone, not both. Land-based zone and threshold training never notices; pool swimmers and multi-device users do.
Dealbreaker? The Polar H10 adds memory and dual Bluetooth ↓
■ Every product has a catch. Verdicts that hide it are how bad buys happen.
Don't buy this if…
- you want a wrist-based optical heart rate watch or GPS running watch, not a chest strapgps running watches dossier →
- you want an armband / optical HR sensor (e.g. for comfort) rather than an electrode chest strapFitness tracker under $100 verdict →
- you want a Garmin GPS running watch and are unsure whether a chest strap is even neededGarmin running watch verdict →
- you want a general fitness tracker for steps, sleep, and casual workoutsfitness trackers under 200 dossier →
Wrong product for you is still a bad buy. These are the cases where we'd send you somewhere else.
Runners-up — if your needs differ
Adjacent verdicts — other needs, same method
Different budget, different household, different job — each of these is already researched, priced and verified. Take the one that matches your need.
Traps — this verdict avoids
Why the Polar H9 is right for you
It avoids every trap below — and for just me, under $80, it is the pick because it delivers:
Swim data vanishes
Only 3 of these 9 straps record swim HR. Bluetooth carries no signal underwater, so unless a strap has onboard memory or store-and-forward — the Polar H10, Garmin HRM 600 and HRM-Pro Plus — the Wahoo TRACKR, Polar H9 and every budget strap lose the entire swim.
Garmin metrics need a Garmin watch
All six running-dynamics metrics stay dark without a Garmin watch. Cadence, ground contact time, vertical oscillation and Step Speed Loss never appear on Apple, Coros, Polar or app-only setups — so a $130-$165 Garmin strap becomes a plain HR belt.
One app at a time
Single-channel budget straps pair to just 1 Bluetooth app at a time. Only the TRACKR, HRM-Pro Plus, HRM 600 and Polar H10 hold 2-3 Bluetooth links at once — feed a watch and a phone together — while ANT+ broadcasts to unlimited receivers.
Provenance — 8 sources, dated
Winners are picked from the full research dossier at knowledgelib.io. Prices, stock and listings are re-verified monthly.