What are Workload Units?
Workload Units (WU) are Bubble.io's consumption-based pricing metric that measures server-side processing capacity used by an application — including database operations, API calls, and backend workflow executions.
How WU Is Calculated
Every server-side operation in Bubble consumes WU. A simple database search costs a fraction of a unit. A recursive workflow that loops through thousands of records can consume hundreds. Bubble allocates a monthly WU budget per plan, and exceeding it either throttles your app or triggers overage charges.
WU Pricing Tiers
Free
Minimal WU allocation, suitable for prototypes and personal projects with low traffic.
Starter / Growth
Moderate WU budgets for early-stage products. Overages begin to appear as user counts grow.
Team
Higher WU limits with some flexibility, but costs scale quickly for data-intensive applications.
Scale / Enterprise
Custom WU allocations with dedicated capacity — often the trigger point for migration decisions.
Common WU Spikes
- Recursive Workflows — Workflows that call themselves in a loop consume WU on every iteration — easy to write, expensive to run
- Unoptimized Searches — Database searches without proper constraints scan entire tables, multiplying WU consumption
- Heavy API Usage — Each external API call through the API Connector counts toward WU, including retries and polling
- Scheduled Workflows — Background jobs running on tight intervals accumulate WU continuously, even during off-peak hours
Related Terms
When WU Costs Signal It's Time to Migrate
When your monthly WU bill approaches or exceeds what a dedicated server would cost, migration becomes financially rational. Relis documents your entire Bubble architecture so your engineering team can rebuild on infrastructure where compute costs scale predictably.