B-series burstable & CPU credits
Low-cost VMs that bank CPU credits while idle and spend them to burst above a baseline.
B-series VMs (Bsv2, Basv2, Bpsv2) run at a low baseline CPU level and accrue credits when under it. When load rises, they spend banked credits to burst toward full core performance. Run consistently hot and you exhaust credits and throttle to baseline.
They are the cheapest way to run small, spiky workloads — dev boxes, low-traffic web servers, build agents — where average CPU is low but occasional bursts matter.
More Azure pricing terms
On-Demand (Pay-As-You-Go)Reserved VM Instance (RI)Savings Plan for ComputeAzure Hybrid Benefit (AHB)Spot Virtual MachinesSpot eviction & eviction policyDev/Test pricingARM region nameMeter & SKUVM series naming (D, E, F, B and s/a/p)Constrained-vCPU sizesEphemeral OS diskCobalt & Ampere (Arm on Azure)vCPUEffective hourly rateWindows vs Linux pricingMax saving %Best price regionNormalized pricing ($/vCPU, $/GB)