# Packet Loss Calculator

> Calculate packet loss as a percentage of packets sent, plus the number lost and the delivery rate, from ping, iperf or interface counters.

Category: IT, networking & security · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/packet-loss-calculator

Packet loss is the share of packets sent that never arrived: (sent − received) ÷ sent × 100. The denominator is always packets sent.

Also called: Packet loss percentage calculator, Packet delivery ratio calculator.

## Inputs
- Packets sent (default 1000)
- Packets received (default 987)

## Results
- Packet loss
- Packets lost
- Delivered

## Formula

```
Loss % = (Sent − Received) ÷ Sent × 100;  Delivered % = Received ÷ Sent × 100
```

Where:
- Sent: packets transmitted
- Received: packets that arrived (duplicates removed)

## Worked example
1. Lost = 1,000 − 987 = 13 packets.
2. Loss = 13 ÷ 1,000 × 100 = 1.3%.

**Result:** 13 of 1,000 packets were lost, a packet loss of 1.3%.

## What the result means

Even small, sustained loss cuts TCP throughput and causes glitches in voice and video. Measure over enough packets: with only 4 pings, one lost reply already shows 25%.

## Assumptions and limits
- Counts come from the same interval at both ends.
- Routers often rate-limit ping replies, so ICMP loss at an intermediate hop does not always mean real traffic is being dropped.

## Questions

### Why can received exceed sent?

Duplicated or retransmitted packets. Remove duplicates before calculating; this calculator rejects received above sent.

### How many packets should I test with?

Hundreds or more. Each lost packet in a 100-packet test moves the result by a whole percentage point.

## Related calculators
- [Network Latency (RTT) Calculator](https://calculators.geekmidst.com/calculators/network-latency-rtt-calculator)
- [Network Throughput Calculator](https://calculators.geekmidst.com/calculators/network-throughput-calculator)
- [Percentage Calculator](https://calculators.geekmidst.com/calculators/percentage-calculator)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/packet-loss-calculator