1 - Root chakra The Root chakra is about being physically there and feeling at home in situations. If it is open, you feel grounded, stable and secure. You don't unnecessarily distrust people. You feel present in the here and now and connected to your physical body. You feel you have sufficient territory.
If you tend to be fearful or nervous, your Root chakra is probably under-active. You'd easily feel unwelcome.
If this chakra is over-active, you may be very materialistic and greedy. You're probably obsessed with being secure and resist change.
The Sacral chakra is about feeling and sexuality. When it is open, your feelings flow freely, and are expressed without you being over-emotional. You are open to intimacy and you can be passionate and lively. You have no problems dealing with your sexuality.
If you tend to be stiff and unemotional or have a "poker face," the Sacral chakra is under-active. You're not very open to people.
If this chakra is over-active, you tend to be emotional all the time. You'll feel emotionally attached to people and you can be very sexual.
The Navel chakra is about asserting yourself in a group. When it is open, you feel in control and you have sufficient self esteem.
When the Navel chakra is under-active, you tend to be passive and indecisive. You're probably timid and don't get what you want.
If this chakra is over-active, you are domineering and probably even aggressive.
The Heart chakra is about love, kindness and affection. When it is open, you are compassionate and friendly, and you work at harmonious relationships.
When your Heart chakra is under-active, you are cold and distant.
If this chakra is over-active, you are suffocating people with your love and your love probably has quite selfish reasons.
The Throat chakra is about self-expression and talking. When it is open, you have no problems expressing yourself, and you might be doing so as an artist.
When this chakra is under-active, you tend not to speak much, and you probably are introverted and shy. Not speaking the truth may block this chakra.
If this chakra is over-active, you tend to speak too much, usually to domineer and keep people at a distance. You're a bad listener if this is the case.
The Third Eye chakra is about insight and visualisation. When it is open, you have a good intuition. You may tend to fantasize.
If it is under-active, you're not very good at thinking for yourself, and you may tend to rely on authorities. You may be rigid in your thinking, relying on beliefs too much. You might even get confused easily.
If this chakra is over-active, you may live in a world of fantasy too much. In excessive cases halucinations are possible.
The Crown chakra is about wisdom and being one with the world. When this chakra is open, you are unprejudiced and quite aware of the world and yourself.
If it is under-active, you're not very aware of spirituality. You're probably quite rigid in your thinking.
If this chakra is over-active, you are probably intellectualizing things too much. You may be addicted to spirituality and are probably ignoring your bodily needs.
Important Announcement
First 
