business APIs

Apache Superset's REST API lets you programmatically manage dashboards, charts, datasets, and database connections in your Superset instance.

Charity Search lets you look up verified US non-profit organizations by name, EIN, or keyword.

Clearbit Logo returns a company logo image by domain name — no scraping required.

Domainsdb.info lets you search registered domain names by keyword, TLD, or zone with no authentication needed.

The Freelancer API lets you post projects, search freelancers, and manage bids and contracts programmatically.

The Gmail API gives you full read/write access to a Gmail inbox via OAuth 2.0 — send messages, read threads, manage labels, and search mail.

Google Analytics Data API (GA4) lets you query sessions, users, and conversion metrics to build custom dashboards or automate reports.

Instatus API lets you programmatically create and update incidents and maintenance windows on your public status page.

Mailchimp API lets you manage email lists, create campaigns, and track subscriber activity.

Mailjet lets you send transactional and marketing emails via a simple REST API using MJML or HTML templates.

Markerapi provides free search access to the USPTO trademark database, letting you check if a brand name is already trademarked.

Redash is an open-source data visualization and dashboarding tool that exposes a REST API for managing queries, data sources, and dashboards programmatically.

Smartsheet's REST API lets you read and write spreadsheet-style data including rows, columns, and attachments from an online work management platform.

Square provides programmatic access to easy way to take payments, manage refunds, and help customers checkout online via REST API.

SwiftKanban is a visual project management platform based on Kanban principles, and its API lets you manage cards, workflows, and board configurations programmatically.

The 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.

The 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.

The 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.

The Tenders in Spain API from tenders.guru delivers Spanish public procurement data in JSON format, covering central government, autonomous communities, and local authorities.

The Tenders in Ukraine API from tenders.guru offers free, unauthenticated access to Ukrainian public procurement data including tender titles, contracting authorities, contract values, and awarded suppliers.

Tomba is an email finding and verification service geared toward B2B sales outreach, letting you look up professional email addresses by name and company domain or verify whether an email address is deliverable.

Trello's REST API gives you full control over boards, lists, and cards, letting you create cards, move them between lists, add attachments, and subscribe to webhooks for real-time events.