You can use this website to plan your dive. For the first dive you will need to enter max depth and time. If you want to plan subsequent repetitive dives, you will have to enter the Surface Interval time so that the software can calculate your Pressure Group at the end of the first dive and at the end of the Surface Interaval. The software will help you calculate the No Decompression Limit for repetitive dives at the desired depth.
The image below shows the inputs and outputs of this page.
Needless to say that scuba diving is an extreme sport and you need to be qualified to go diving.
This script assumes that you are starting your dive planning without any residual Nitrogen from previous dives in your body. This assumption is correct as long as this is your first dive for at least 24 hrs, it it not at altitude and you have not been flying in the last 24 hrs.
This section calculates your maximum No Decompression Limit for a given depth and also your pressure group after a dive at that depth for a user defined bottom time.
Your post-Dive Pressure Group is:
and
Your Maximum Bottom Time (NDL) in minutes is:
and
Your Decompression Stop @ 6m is:
Your post Surface Interval Pressure Group is:
Your NDL for this dive is:
and
Your Residual Nitrogen Time (RNT) in minutes is:
Your Post Dive Pressure Group is:
and
Your Decompression Stop @ 6m is:
Your post Surface Interval Pressure Group is:
Your NDL for this dive is:
and
Your Residual Nitrogen Time (RNT) in minutes is:
Your Post Dive Pressure Group is:
and
Your Decompression Stop @ 6m is:
To validate that this page produces correct results you can use the resources below