Laser Peak Power Calculator

Calculator Inputs

Use the mode selector to calculate from pulse energy or from average power and repetition rate.

Reset

Calculation Mode

Choose the input path that matches your laser data sheet.

Pulse Shape Assumption

Shape factor adjusts the peak estimate from the same pulse energy.

Pulse Duration

Pulse Energy

Required when using pulse energy mode.

Average Power

Required when using average power mode.

Repetition Rate

Optional in energy mode. Required in average power mode.

Beam Diameter

Used for beam area, intensity, and fluence.

Wavelength

Used to estimate photons per pulse.

Formula Used

For a pulsed laser, peak power is estimated from pulse energy divided by pulse duration, then adjusted by the pulse shape factor.

Peak Power = Shape Factor × (Pulse Energy ÷ Pulse Duration) Pulse Energy = Average Power ÷ Repetition Rate Average Power = Pulse Energy × Repetition Rate Beam Area = π × (Beam Diameter ÷ 2)² Peak Intensity = Peak Power ÷ Beam Area Fluence = Pulse Energy ÷ Beam Area Photons per Pulse = Pulse Energy ÷ (h × c ÷ λ)

Shape factor guide

Top-Hat pulse: 1.00
Gaussian pulse using FWHM duration: 0.94
Sech² pulse using FWHM duration: 0.88
Super-Gaussian pulse: 0.97

How to Use This Calculator

Choose whether you know pulse energy directly or only average power and repetition rate.
Enter pulse duration and select the correct time unit.
Pick the pulse shape that best matches your laser pulse model.
Optionally enter beam diameter to estimate peak intensity and fluence.
Optionally enter wavelength to estimate photons delivered in each pulse.
Submit the form to view the result block, chart, and export buttons above the calculator.

Example Data Table

Example	Pulse Energy	Pulse Duration	Rep Rate	Shape	Approx. Peak Power
Q-switched lab source	120 uJ	8 ns	20 kHz	Top-Hat	15.0 kW
Ultrafast amplifier	250 uJ	300 fs	1 kHz	Gaussian	783 MW
Fiber pulse source	50 uJ	10 ps	500 kHz	Gaussian	4.70 MW
Mode-locked oscillator	8 nJ	120 fs	80 MHz	Sech²	58.7 kW

Frequently Asked Questions

1. What does peak power mean for a laser pulse?

Peak power is the highest instantaneous power inside one pulse. It can be far larger than average power because the same energy is compressed into a very short time.

2. Why is pulse duration so important?

Peak power rises sharply as pulse duration shrinks. Halving the duration roughly doubles peak power when pulse energy remains constant.

3. Why are pulse-shape factors included?

Different pulse envelopes spread energy differently in time. A Gaussian pulse and a top-hat pulse with the same energy and FWHM do not share the same true peak value.

4. When should I enter beam diameter?

Enter beam diameter when you need peak intensity or fluence. Those quantities depend on how the pulse energy or power is distributed across the beam spot area.

5. What is the difference between peak power and average power?

Average power is the time-averaged output over many pulses. Peak power describes the top of an individual pulse and can be orders of magnitude higher.

6. Can this tool work with femtosecond pulses?

Yes. The duration unit list includes fs and ps ranges, so the calculator can estimate ultrafast pulse peak power and related beam quantities.

7. Why is repetition rate optional in one mode?

If pulse energy is already known, peak power only needs energy, duration, and the shape factor. Repetition rate becomes useful for average power and duty-cycle estimates.

8. Does this replace a full laser characterization setup?

No. It is a design and estimation tool. Real systems can differ because of pulse asymmetry, chirp, beam quality, clipping, and measurement uncertainty.