Sentiment Analysis API

Fast English sentiment analysis: positive, negative or neutral label, a -1 to +1 score and per-sentence results. Rule-based (VADER), deterministic, no AI costs.

Authentication & base URL

Subscribe through one of our marketplace listings; your marketplace API key and base URL are shown there. All endpoints return JSON over HTTPS, served from a global edge network (typically 20–150 ms).

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Endpoints

GET `/v1/sentiment`

Analyze sentiment

Parameter	In	Description	Example
`text` *	query	Text to analyze (max 20,000 characters)	`The food was great but the service was painfully slow.`
`sentences`	query	Include per-sentence results (true/false, default true)	`true`

POST `/v1/sentiment`

Analyze sentiment (long text in body)

Request body: text/plain

Parameter	In	Description	Example
`sentences`	query	Include per-sentence results (true/false)	`true`

Example

GET /v1/sentiment?text=The+food+was+great+but+the+service+was+painfully+slow.&sentences=true

{
  "label": "negative",
  "score": -0.4678,
  "positive": 0.168,
  "negative": 0.304,
  "neutral": 0.528,
  "language": "en",
  "note": "Lexicon and rule-based (VADER) English sentiment: fast, deterministic, no AI costs. Score from -1 (most negative) to +1 (most positive)."
}

Fast English sentiment analysis: positive, negative or neutral label, a -1 to +1 score and per-sentence results. Rule-based (VADER), deterministic, no AI costs.

Use cases

Product reviews and NPS comments, social media monitoring, support tickets triage, chatbot tone checks, dashboards of customer feedback.

Why this API

Accurate on short, informal text: understands negations ("not bad"), intensifiers ("very good"), CAPS, "but" clauses, punctuation, emoticons and emojis.
Fast and cheap: no AI model calls, runs on a global edge network.
Per-sentence scores to find what people liked and disliked.

Pricing

Free plan with 500 calls per month, then Pro (25,000 calls for $4.99/month) and Ultra (150,000 calls for $14.99/month). See all plans.