For a quick background on cosmic or true sidereal vs tropical human design, check out this post.
If you need to get your charts, you can get your tropical human design chart at Genetic Matrix (affiliate link) and your true sidereal / cosmic human design chart at Cosmic Human Design.
(I previously wrote a very in depth comparison of my different charts, which you can read here, and wrote a follow-up here.)
Okay, now that you have both charts, let’s get into how to tell which one is right for you.
1. Experiment
As with all things human design, it’s going to come down to your own individual experimentation.
Note any differences in your type, strategy, authority, and open centers.
Open centers are where we’re more open to influence. So, for example, do you have a defined head center in one chart and it’s open in the other?
Next, identify your channels and whether there are any differences here, as well as, your definition (single, split, triple-split, etc.).
If you’re familiar with cognition, determination, and environment, identify any changes in these areas, too.
2. Self-reflection
Focus on what feels true for you and each chart does or does not reflect that back to you (Note: this is different from focusing on what the chart is telling you about yourself. Charts are reflective tools, not prescriptive definitions.)
If one chart shows you as an energy type and the other as a non-energy type, that’s really easy to experiment with.
If your authority is different, for example, from splenic to sacral, try changing how you make decisions and see how it feels.
For each area of difference, think back to times in your past that might be indicative of each chart.
In terms of definition, do you feel complete on your own (single definition), or do you feel you need others to “feel complete?” (Let’s also acknowledge that this question is more nuanced than a simple yes/no, especially with various ways we’ve been raised and learned to relate to ourselves and others.)
This site is great for reading descriptions of each gate and channel.
3. Do your own research
Take some time to really dig into the tropical and true sidereal approaches. Does one resonate more? Just because someone you know is adamant that one is better or “more accurate” than the other, really try to see for yourself.
Do the approaches themselves make sense to you?
4. Cross-reference with other tools that you find helpful
Some examples could be your personal numerology and your astrological natal chart.
Since your natal chart might bring up more questions about whether to use tropical or true sidereal, or the placidus or whole sign house system, it might be more helpful in this scenario to focus on tools that don’t rely on planetary positions or birth location.
Numerology only uses your full name and your date of birth.
I used Kaitlyn Kaerhart’s easy-to-follow book, You Are Cosmic Code to calculate my personal numerology. She also shares helpful resources on her Instagram page for calculating and understanding your numbers.
5. Remember that you don’t actually have to choose a chart
You can just live your life. If a chart happens to give you the language and tools to understand yourself better, that’s great. But you don’t have to make a decision about which human design chart is right for you.
If you like having your human design chart to refer back to as part of your own self-reflection, why not check in with both of them? You don’t have to decide or know right now.
Release the pressure to know.
Remember that your chart does not replace or take precedence over your own intuition.
Developing my own intuitive abilities has been incredible for me and more helpful than any chart.