Calculator
Will your B2B store hit your ERP’s API limits?
Enter a few numbers about your store and pick your ERP. You’ll see how many API calls a day the integration makes, how your busiest minute compares with the limit, and what to change first if it doesn’t fit.
Interactive
Sync budget calculator
How many API calls a day your store would make, against your ERP’s published limits.
How we work it out
No hidden multipliers. These are the sums behind every number in the calculator.
For what to do with the result, read our guide to ERP integration for B2B ecommerce.
- Sending orders = orders a day × API calls per order.
- Checking stock = 1,440 minutes in a day ÷ minutes between checks, around the clock. Zero when your ERP sends webhooks.
- Live lookups = the calls made while a buyer waits, such as a live price or account balance.
- Full refreshes = (products + customers) ÷ 100 records per call, rounded up, × refreshes a day.
- Busiest minute = orders in that minute × calls per order, plus live lookups spread over an 8-hour trading day.
- The verdict uses whichever limit is closest: under 60% fits comfortably, up to 100% is tight, and over 100% is over the limit. Retries aren’t counted, so leave room for them.
About this calculator
Where do the API limits come from?
From each vendor’s own developer documentation, checked in October 2026. The calculator links to the source for whichever system you pick. Vendors change their limits, so check the source before you rely on a number.
Why aren’t MYOB, Pronto Xi or Options in the list?
They don’t publish numeric limits to calculate against. MYOB applies per-second and daily limits per API key without listing the numbers, and on-premises systems such as Pronto Xi, Options and SAP Business One are limited by your own server. Ask your ERP partner what load the integration can safely add.
What counts as an API call?
Every request the integration sends to the ERP: reading a page of products, creating an invoice, applying a payment, or checking a price while a buyer waits. One online order usually takes several calls.
What should we do if we’re over the limit?
Queue writes so bursts go out at a steady rate, cache prices and balances in the store instead of asking the ERP live, use webhooks instead of polling, and fetch only what changed. The calculator shows which of these saves the most for your numbers.
Does TierCommerce stay within these limits?
Yes. Our integrations queue writes, cache what changes rarely and fetch only what changed, so they stay inside each ERP’s limits as order volume grows. Book a demo and we’ll show you the sync log on your own ERP.
See TierCommerce running on your own products.
Bring a price list and a recent purchase order. We’ll show you both working in 30 minutes.