Free Online Erlang C Calculator
Instantly calculate your call centre staffing needs — no downloads, no spreadsheets, just fast answers. Our free calculator gives you accurate staff requirements in seconds so you can optimise service levels and improve forecasting accuracy.
This is a simplified version of the Staffing Levels Simulator — one of 10 professional WFM tools available to ACXPA Members.
, You're Using the Free Erlang Calculator
This is a simplified version of just one of 10 professional WFM tools available to ACXPA Individual Members. Use it below to calculate staffing needs — then see what you'd unlock with a full membership.
As a subscriber, you also get discounts on WFM training courses — links below apply them automatically.
, This Is the Free Version — You've Got the Advanced Suite
This calculator is the simplified public version of the Staffing Levels Simulator inside your Members' WFM Hub. Your version updates live as you move the sliders, adds ASA, occupancy, probability of waiting and queue time, charts how agent numbers change your service level and gives you a PDF, with every other WFM tool alongside it.
Online Erlang C Calculator
Our calculator will instantly show you how many staff you need on the phones — plus headcount after shrinkage. No spreadsheets, no stress.
Want to see why 15 agents is never enough?
Justin Tippett walks through Erlang C with one simple scenario. See what one late agent, 20 extra seconds of handle time or 10% more calls really does to your service level.
See what it coversWant to see why 15 agents is never enough?
Justin Tippett walks through Erlang C with one simple scenario. Upgrade your membership to watch it, then run the same numbers on your own centre in the WFM Hub.
See what it coversWant to prove what any change will do to wait times?
Erlang C explained in 12 minutes. Every scenario comes from the Service Levels Simulator, so you can run the same numbers on your own centre straight after.
Watch the Member Byte10 Professional WFM Tools Available to Members
This free calculator is just the tip of the iceberg. ACXPA Individual Members unlock the full suite of professional workforce planning tools.
Advanced Staffing Levels Simulator
The members' version of the calculator above, with live sliders, ASA, occupancy, queue time and a PDF of your results.
Workload & Capacity Planner
Convert volume and AHT into minimum FTE once you factor in shrinkage, occupancy and concurrency.
Service Level Simulator
Enter your current team size and see the service levels your current staffing can realistically achieve.
Interval Planner
Stress-test your operation by modelling volume, AHT and staffing scenarios across intervals.
Outlier Detection Wizard
Pinpoint top and bottom performers across multiple metrics to focus your coaching effort.
Shrinkage Calculator
Turn leave, meetings and training hours into an accurate shrinkage % for smarter planning.
Employee Replacement Calculator
Quantify the true cost of turnover — from exit interviews through to full productivity.
Employee Turnover Calculator
Measure attrition and retention against real contact centre benchmarks.
Employee Cost Calculator
See what an employee really costs per year, hour and minute, with on-costs included.
Per Minute Cost Calculator
Turn a few wasted seconds per call into dollars and lost FTE.
Ready for Professional-Grade WFM Tools?
Explore ACXPA memberships for instant access to the full WFM Hub — plus roundtables, benchmarking reports, training discounts, the full resource library and more.
Keep Learning & Exploring
Free resources to help you get more value from the calculator above.
Learn About Erlang
The science behind call centre forecasting, staffing and service levels — explained in plain English.
WFM Training Courses
Upskill in forecasting, scheduling and real-world workforce optimisation — online with expert trainers.
Free Call Centre Hub
Free guides, templates, glossaries and industry data for contact centre professionals — no account required.
Want the full WFM planning toolkit?
The free calculator gives you a quick agent count. The WFM Hub has 11 online tools that go further: staffing levels, service levels, shrinkage, and interval-by-interval planning for busy days.
4 are free to use now. ACXPA Members get all 11 in full, plus 25% off live WFM training.
What You'd Unlock as an Individual Member
Full access to all 10 full-version WFM tools the moment you upgrade — no waiting, no setup.
Advanced Staffing Levels Simulator
The members' version of the calculator above, with live sliders, ASA, occupancy, queue time and a PDF of your results.
Workload & Capacity Planner
Convert volume and AHT into minimum FTE with shrinkage, occupancy and concurrency applied.
Service Level Simulator
See the service levels your current staffing can realistically achieve before you go live.
Interval Planner
Model how changes in volume, AHT or staffing ripple through your operation interval by interval.
Outlier Detection Wizard
Identify top and bottom performers across multiple KPIs so coaching effort lands where it matters most.
Shrinkage Calculator
Build an accurate shrinkage % from leave, meetings, training and daily interruptions.
Employee Replacement Calculator
Quantify the true cost of losing an employee — from exit interviews through to full productivity.
Employee Turnover Calculator
Benchmark your attrition and retention rates against real contact centre data.
Employee Cost Calculator
See what an employee really costs per year, hour and minute, with on-costs included.
Per Minute Cost Calculator
Turn a few wasted seconds per call into dollars and lost FTE.
Ready to Unlock the Full WFM Hub?
Upgrade to Individual Membership for instant access to all 10 tools — plus roundtables, benchmarking reports, training discounts and more.
Available to You Right Now
Resources available to subscribers — WFM training links are personalised to apply your subscriber discount.
Learn About Erlang
The science behind call centre forecasting, staffing and service levels — explained in plain English.
WFM Training Courses
Upskill in forecasting, scheduling and real-world workforce optimisation — with your subscriber discount applied.
Call Centre Hub
Free guides, templates, glossaries and industry data — your subscriber access to the contact centre resource hub.
Want to plan beyond a single agent count, ?
Your free account includes the Erlang C Calculator (Free) for Excel. Enter your calls, handle time and service level target, and see the agents you need and the staff to roster.
Upgrade to unlock the staffing, service level, shrinkage and interval planners in the WFM Hub, all online, with no spreadsheet to maintain.
Go to Your WFM Hub
Access your complete suite of professional WFM tools — staffing simulators, capacity planners, shrinkage, turnover, outlier detection and more. New tools are added regularly.
More Member Resources
Training links are personalised to apply your member discount automatically.
Members' Call Centre Hub
Your exclusive member hub with roundtables, industry data, benchmarking and contact centre resources.
WFM Training Courses
Live and self-paced WFM training — your member discount is applied automatically.
Learn About Erlang
The science behind call centre forecasting, staffing and service levels — in plain English.
