kitio.aiAmazon Comprehend vs IBM Watson Natural Language Understanding
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Amazon Comprehend starts at See pricing page and IBM Watson Natural Language Understanding starts at See pricing page. Check both pricing pages for current plans.
IBM text analytics API for entities, sentiment, emotion and categories
FreemiumAt a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Entity and key phrase extraction
- Sentiment analysis
- Custom classification
- Custom entity recognition
- Topic modeling
- Entity and keyword extraction
- Sentiment and emotion analysis
- Category classification
- Custom classification models
- Semantic role parsing
| Feature | Amazon Comprehend | IBM Watson Natural Language Understanding |
|---|---|---|
| Best for | AWS natural language API for entities, sentiment and classification | IBM text analytics API for entities, sentiment, emotion and categories |
| Category | Data & analytics | Data & analytics |
| Pricing model | Freemium | Freemium |
| Starting price | See pricing page | See pricing page |
| Free plan | Yes | Yes |
| Made by | Amazon Web Services | IBM |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
Amazon Comprehend starts at See pricing page and IBM Watson Natural Language Understanding starts at See pricing page. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
Free Tier
Free
- 50K units of text per API monthly
- First 12 months only
Standard APIs
$0.0001 / unit (100 characters)
- Entities, sentiment, key phrases
- Volume discounts at scale
Custom models
$3 / training hour
- Endpoint inference billed per second
- Monthly model storage fee
2 plans
Lite
Free
- 30,000 NLU items a month
- One custom model
Standard
$0.003 / NLU item
- Scales past 5M items a month
- Custom classification models at $25
- Custom entity models at $800
Prices in USD, checked Nov 5, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
Amazon Comprehend
- No ML expertise needed for basic APIs
- Custom models on your own labels
- Scales with other AWS services
- Free tier lasts only 12 months
- Custom models have no free tier
- Costs can be hard to estimate
IBM Watson Natural Language Understanding
- Permanent free Lite plan
- Wide range of text analysis features
- Managed or self-hosted options
- Lite instance pauses after 30,000 items
- Custom entity models cost extra
- Some features still in beta
Which one should you choose?
Choose Amazon Comprehend if you want:
- No ML expertise needed for basic APIs
- Custom models on your own labels
- Scales with other AWS services
Watch out: free tier lasts only 12 months.
Choose IBM Watson Natural Language Understanding if you want:
- Permanent free Lite plan
- Wide range of text analysis features
- Managed or self-hosted options
Watch out: lite instance pauses after 30,000 items.
Amazon Comprehend vs IBM Watson Natural Language Understanding FAQ
What is the difference between Amazon Comprehend and IBM Watson Natural Language Understanding?
Amazon Comprehend: AWS natural language API for entities, sentiment and classification. IBM Watson Natural Language Understanding: IBM text analytics API for entities, sentiment, emotion and categories. Both are data & analytics tools.
Is Amazon Comprehend or IBM Watson Natural Language Understanding cheaper?
Amazon Comprehend starts at See pricing page and IBM Watson Natural Language Understanding starts at See pricing page. Check both pricing pages for current plans.
Do Amazon Comprehend and IBM Watson Natural Language Understanding have free plans?
Amazon Comprehend: Yes. IBM Watson Natural Language Understanding: Yes.
Who makes Amazon Comprehend?
Amazon Comprehend is made by Amazon Web Services, based in United States.
Who makes IBM Watson Natural Language Understanding?
IBM Watson Natural Language Understanding is made by IBM, based in United States.
Which should I choose, Amazon Comprehend or IBM Watson Natural Language Understanding?
Choose Amazon Comprehend if you value no ml expertise needed for basic apis and custom models on your own labels. Choose IBM Watson Natural Language Understanding if you value permanent free lite plan and wide range of text analysis features.