---
title: "Peak Power & Fluence calculator — AperiOptic"
description: "Peak power, pulse energy and fluence from average power. Free online optics calculator, with the formula and code snippets."
url: "https://aperioptic.com/calculators/peak-power-fluence"
---

# Peak Power & Fluence calculator

Peak power, pulse energy and fluence from average power.

Category: [Laser & Ultrafast](https://aperioptic.com/calculators)

Formula: `Ep = Pavg/frep · Ppk = Ep/τ`

## Inputs

| Input | Parameter | Unit | Default |
| --- | --- | --- | --- |
| Avg power | `Pavg` | mW | 100 |
| Rep rate | `frep` | MHz | 80 |
| Pulse width | `tau` | fs | 100 |
| Spot Ø | `D` | µm | 50 |

## Result with the default inputs

- Pulse energy: 1.25 nJ
- Peak power (Ep/τ): 12.5 kW
- Peak power (Gaussian): 11.743 kW
- Fluence (avg over Ø): 0.0637 mJ/cm²
- Peak fluence (Gaussian): 0.1273 mJ/cm²

Open it with your own values: put each input in the address as a parameter, for example [`/calculators/peak-power-fluence?Pavg=100`](https://aperioptic.com/calculators/peak-power-fluence?Pavg=100). A unit other than the listed one goes in `<parameter>_unit`.

Read more: [Wikipedia: Pulse (signal processing), Pulse shapes](https://en.wikipedia.org/wiki/Pulse_(signal_processing)#Pulse_shapes)

[All optics calculators](https://aperioptic.com/calculators)

---

The interactive page: https://aperioptic.com/calculators/peak-power-fluence (AperiOptic runs in the browser; free, no account). Every page of the site as Markdown: https://aperioptic.com/llms.txt