Text Similarity
Estimate how much two texts overlap using shared vocabulary.
About Text Similarity
The shared word set is measured against combined and union counts to express how much the texts overlap proportionally. Spotting overlap early catches accidental repetition or near-duplicate sections before content gets flagged as recycled.
Formula
Text Similarity
Dice similarity = 2 x overlap / (A + B); Jaccard = overlap / (A + B - overlap)
- overlap
- Vocabulary the two texts share
Worked example
With the default values below, Text Similarity returns Similarity of 26.7%. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Text A wordsminimum 1
- 800
- Text B wordsminimum 1
- 700
- Words in commonminimum 0
- 200
Results
- Similarity
- 26.7%
- Jaccard Index
- 15.4%
- Overlap Words
- 200.00
Step by step
- 1Values used
- 2Text Similarity
- 3Similarity= 26.7
- 4Jaccard Index= 15.4
- 5Overlap Words= 200.00
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Text Similarity calculated?
Dice similarity = 2 x overlap / (A + B); Jaccard = overlap / (A + B - overlap) The shared word set is measured against combined and union counts to express how much the texts overlap proportionally.
Why does Text Similarity matter?
Spotting overlap early catches accidental repetition or near-duplicate sections before content gets flagged as recycled.
What values do I need to enter?
This calculator takes 3 inputs: Text A words, Text B words, Words in common. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.