How to use the Sentiment Analyzer (Lexicon Based)
- 1. Paste English textAdd a review, comment, tweet or survey answer.
- 2. AnalyseThe tool scores known words and adjusts for negations and intensifiers.
- 3. Check the reasonsSee each word's score and the overall label.
How the score is calculated
The analyzer uses a word list of about 200 English words, each scored from −3 (very negative) to +3 (very positive). It adds the scores, with two adjustments: a negation such as not or never within the three words before flips the sign, and an intensifier such as very or really right before multiplies it. The total is turned into a compound score with compound = raw ÷ √(raw² + 15), the same normalisation idea VADER uses.
Worked example: "really good" scores 2 × 1.5 = 3, "helpful" scores 2 and "not clean" scores −2. The raw total is 3, so compound = 3 ÷ √24 = 0.6124, which is Positive (above 0.05).
What it can and cannot do
- Good for: quick triage of reviews, teaching how lexicon models work, spotting which words drive a score.
- Misses sarcasm: "Great, another delay" counts as positive for "great".
- English only: Hindi, Hinglish, emojis and slang are not scored.
- No context: it does not understand topics, so "killer feature" would not be read as praise.
This is not an AI model and does not send your text anywhere. For serious work, teams train or fine-tune machine learning models on labelled examples from their own domain. Clean text before analysis with the text preprocessing tool, or find frequent phrases with the n-gram generator.
Frequently asked questions
Is this the VADER library?
No. It borrows VADER's compound normalisation idea but uses its own smaller word list written for this tool.
Why is a sentence Neutral?
None of its words are in the list, or positive and negative words cancel out.
Is the Sentiment Analyzer (Lexicon Based) free?
Yes, the Sentiment Analyzer (Lexicon Based) is free. The first time you see your first result, you are asked for your name and WhatsApp number once. After that, this and every other Uncodemy tool opens straight away without the form.