Load Balancer Connections Per Second Calculator

Work out load balancer connections per second instantly with clear inputs, formula shown and shareable results.

About Load Balancer Connections Per Second Calculator

Load balancers are rated separately for requests per second, connections per second and TLS handshakes per second, and the TLS figure is usually the binding one because an asymmetric key operation is orders of magnitude more expensive than forwarding a request. Keep-alive amortises connection setup across requests, and session resumption removes most full handshakes.

Formula

Connection rate

new connections per second = requests per second / requests per connection; TLS handshakes = connections x full-handshake share

Worked example

With the default values below, Load Balancer Connections Per Second Calculator returns New connections per second of 2,500. Change any input above and every figure here is recalculated in your browser.

Inputs used

Requests per secondminimum 0.001 req/s: 20,000 req/s
Requests per connection (keep-alive)minimum 1: 8
Share needing a full TLS handshakeaccepts 0–100 %: 20 %
Device TLS handshake capacityminimum 1 cps: 6,000 cps

Results

New connections per second: 2,500 cps
Full TLS handshakes per second: 500 cps
TLS capacity utilisation: 8.3%
Assessment: Within device TLS handshake capacity

Step by step

1Values used
2Connection rate
3New connections per second= 2,500 cps
4Full TLS handshakes per second= 500 cps
5TLS capacity utilisation= 8.3
6Assessment= Within device TLS handshake capacity

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is TLS handshake load reduced?

Session resumption with tickets, keep-alive to amortise connections, TLS 1.3 which needs one round trip, and ECDSA certificates which are far cheaper than RSA to sign with.

Why does the datasheet RPS figure not help?

Because it is measured with keep-alive and resumed sessions. Real traffic with many new clients hits the connection and handshake limits long before the request limit.