Calculate Text Entropy
Free online text entropy calculator. Measure Shannon entropy, information density, and randomness of any text in bits per character.
Character Frequency Distribution
About This Free Online Calculate Text Entropy
Our free text entropy calculator computes the Shannon entropy of your text, measuring its information density and randomness in bits per character. Higher entropy means more randomness and information per character; lower entropy means more predictability and redundancy. This tool is useful for analyzing encrypted text, testing password strength, evaluating compression potential, studying language patterns, or any application involving information theory. Also provides character frequency distribution to show which characters contribute most to the total entropy.
Features of Our Calculate Text Entropy
- Shannon entropy in bits per character
- Total entropy in bits and bytes
- Character frequency distribution table
- Entropy as percentage of maximum
- Unique character count
- Real-time calculation as you type
How to Use the Calculate Text Entropy
The Calculate Text Entropy works right in your browser — no signup, no installation. Follow these steps:
- Paste or type text to analyze.
- View Shannon entropy in bits per character and total bits.
- Check the character frequency distribution table.
- Use Copy to save results.
Frequently Asked Questions About Calculate Text Entropy
What is Shannon entropy?
Shannon entropy measures the average information content of each character in bits. Higher values mean more randomness. English text typically scores 3.5-5 bits/char. Random strings approach log2(alphabet size).
What does a high entropy value mean?
High entropy (~7+ bits/char for ASCII) indicates random or encrypted text with little predictability. Low entropy (~2-4 bits) indicates highly patterned text like natural language.
Why Choose the Calculate Text Entropy?
Good analysis needs to be both fast and private. The Calculate Text Entropy processes your text locally and shows results as you work, so you can iterate on drafts and data freely, knowing the content is never transmitted or stored.