How to Choose the Best Business API in 2026
There are 23 Business APIs in our directory. Of these, 7 require no authentication, making them ideal for quick prototyping. 7 are rated beginner-friendly.
Scores last tested: 2026-07-23
Quick Comparison: Top 10 Business APIs
Ranked by API Score. Measured means we called a real endpoint of that API; Est. means the score is derived from metadata because the endpoint could not be called without credentials. Discontinued APIs are excluded.
| Name | API Score | Auth | HTTPS | CORS | Difficulty |
|---|---|---|---|---|---|
| Apache Superset | 87 A Est. | API Key | ✓ | ✓ | Intermediate |
| Redash | 82 A Est. | API Key | ✓ | ✓ | Intermediate |
| Tenders in Hungary | 82 A Est. | No Auth | ✓ | ? | Beginner |
| Tenders in Poland | 82 A Est. | No Auth | ✓ | ? | Beginner |
| Tenders in Romania | 82 A Est. | No Auth | ✓ | ? | Beginner |
| Tenders in Spain | 82 A Est. | No Auth | ✓ | ? | Beginner |
| Tenders in Ukraine | 82 A Est. | No Auth | ✓ | ? | Beginner |
| Domainsdb.info | 79 B Est. | No Auth | ✓ | ✗ | Beginner |
| Clearbit Logo | 77 B Est. | API Key | ✓ | ? | Intermediate |
| Tomba email finder | 77 B Est. | API Key | ✓ | ✓ | Intermediate |
Free Business APIs (No Auth)
These APIs require no API key or signup. Start using them immediately.
Domainsdb.info
⭐ Beginner's PickDomainsdb.info lets you search registered domain names by keyword, TLD, or zone with no authentication needed.
markerapi
⭐ Beginner's PickMarkerapi provides free search access to the USPTO trademark database, letting you check if a brand name is already trademarked.
Tenders in Hungary
⭐ Beginner's PickThe Tenders in Hungary API from tenders.guru delivers publicly available government procurement data for Hungary, including contract values, buyer and supplier names, and tender dates.
Tenders in Poland
⭐ Beginner's PickThe Tenders in Poland API provides structured access to Polish government procurement notices and contract awards from tenders.guru, covering public sector buyers across all regions of Poland.
Tenders in Romania
⭐ Beginner's PickThe Tenders in Romania API by tenders.guru exposes Romanian public procurement data including tender details, contract values, and awarded suppliers, all freely accessible without authentication.
Tenders in Spain
⭐ Beginner's PickThe Tenders in Spain API from tenders.guru delivers Spanish public procurement data in JSON format, covering central government, autonomous communities, and local authorities.
Try It in 5 Minutes: Domainsdb.info
Quick implementation example using Domainsdb.info.
Using curl
curl "https://api.domainsdb.info/v1/domains/search?domain=openai&zone=com&limit=10"
JavaScript
const url = "https://api.domainsdb.info/v1/domains/search?domain=openai&zone=com&limit=10";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data); New to APIs? Read our Getting Started Guide →
Frequently Asked Questions
How many Business APIs are available?
There are 23 Business APIs in our directory as of 2026.
Are there free Business APIs?
Yes, 7 Business APIs require no authentication and are completely free to use.
What is the easiest Business API to use?
Domainsdb.info is one of the easiest to get started with. It is rated as beginner-level and requires no authentication.
Do I need an API key for Business APIs?
It depends. 7 APIs need no authentication, 10 require an API key, and 6 use OAuth.