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<p>Boron isotope systematics of planktonic foraminifera from core-top sediments and culture experiments have been studied to investigate the sensitivity of <span class="inline-formula"><i>δ</i>¹¹B</span> of calcite tests to seawater pH. However, our knowledge of the relationship between <span class="inline-formula"><i>δ</i>¹¹B</span> and pH remains incomplete for many taxa. Thus, to expand the potential scope of application of this proxy, we report <span class="inline-formula"><i>δ</i>¹¹B</span> data for seven different species of planktonic foraminifera from sediment core tops. We utilize a method for the measurement of small samples of foraminifera and calculate the <span class="inline-formula"><i>δ</i>¹¹B</span>-calcite sensitivity to pH for <i>Globigerinoides ruber</i>, <i>Trilobus sacculifer</i> (sacc or without sacc), <i>Orbulina universa</i>, <i>Pulleniatina obliquiloculata</i>, <i>Neogloboquadrina dutertrei</i>, <i>Globorotalia menardii</i>, and <i>Globorotalia tumida,</i> including for unstudied core tops and species. These taxa have diverse ecological preferences and are from sites that span a range of oceanographic regimes, including some that are in regions of air–sea equilibrium and others that are out of equilibrium with the atmosphere. The sensitivity of <span class="inline-formula"><i>δ</i>¹¹B</span><span class="inline-formula">_carbonate</span> to <span class="inline-formula"><i>δ</i>¹¹B</span><span class="inline-formula">_borate</span> (e.g., <span class="inline-formula">Δ<i>δ</i>¹¹B_carbonate∕Δ<i>δ</i>¹¹B_borate</span>) in core tops is consistent with previous studies for <i>T. sacculifer</i> and <i>G. ruber</i> and close to unity for <i>N. dutertrei</i>, <i>O. universa</i>, and combined deep-dwelling species. Deep-dwelling species closely follow the core-top calibration for <i>O. universa</i>, which is attributed to respiration-driven microenvironments likely caused by light limitation and/or symbiont–host interactions. Our data support the premise that utilizing boron isotope measurements of multiple species within a sediment core can be utilized to constrain vertical profiles of pH and <span class="inline-formula"><i>p</i>CO₂</span> at sites spanning different oceanic regimes, thereby constraining changes in vertical pH gradients and yielding insights into the past behavior of the oceanic carbon pumps.</p>