Erlang C Alternatives: Smarter, Simpler Ways to Calculate Staffing

Tired of wrestling with Erlang C spreadsheets and endless formulas? Discover smarter, modern alternatives that calculate your contact-center staffing in seconds — no math degree required.

What Erlang C Is (and Why It Still Exists)

Erlang C has been around since 1917. It’s the formula contact-center leaders use to predict how many agents they need based on call volume, handle time, and target service level.

The idea is simple: use math to find balance between staffing and service.

But here’s the reality — Erlang C was built for a world where:

• Volume is consistent every hour.

• Agents only take phone calls.

• Everyone works the same shift length.

• Breaks, absenteeism, and multitasking don’t exist.

If that sounds nothing like your contact center today, you’re not alone.

Why Erlang C Falls Short for Modern Teams

Most small and mid-sized contact centers start with an Erlang C calculator they found online or in Excel. And it does work… until you realize how many assumptions it gets wrong.

Here’s the problem:

• It ignores shrinkage. Breaks, meetings, and absences aren’t included.

• It can’t handle multichannel volume. Do your agents handle email, chat, and SMS? Not part of the math.

• It’s static. One formula = one moment in time. Change your inputs, rebuild everything.

Even for call-only environments, the math can feel detached from real life. A one-person difference can swing service level by 20%, but Erlang C won’t show you where or why.

Spark Queue: The Visual Alternative to Erlang C

For lean contact centers, Spark Queue simplifies the same calculation Erlang C tries to handle — without the spreadsheet headache.

Here’s how it works:

1. Input your hourly volume and average handle time.

2. Adjust your service level goal (e.g. 80/30).

3. Set your shrinkage for breaks, meetings, and PTO.

4. See exactly how many agents you need each hour — no formulas, no macros.

5. Build actual schedules on top of those staffing needs and watch your coverage update in real time.

It’s like watching Erlang C come to life — but built for the realities of today’s hybrid, multichannel, dynamic teams. Oh and you'll get a bit of your sanity back.

Final Thoughts

Erlang C isn’t wrong — but you shouldn't be using only an Erlang C calculator by itself to determine staffing levels in your call center.

If you’ve ever thought, “there has to be an easier way,” there is.

Stop wrestling with spreadsheets and static calculators.

See your coverage, schedules, and staffing gaps in real time.

👉 Try Spark Queue — the modern alternative to Erlang C.