Requestly

Top 10 Communication & Messaging APIs

Ranked by popularity score. A comparison view generated from structured frontmatter (pricing, auth, docs links).

RankAPIFree tierStarting fromAuthDetails
1
Gmail API
Send, read, and manage Gmail emails programmatically. Build email clients, automate workflows, and integrate email into your applications.
YesFreeoauth2View
2
WhatsApp API
Send and receive WhatsApp messages programmatically with the official Business API for customer engagement and support.
YesFree for first 1,000 conversations/monthoauth2View
3
Discord API
Build Discord bots and integrations to manage servers, send messages, handle events, and create interactive experiences for communities.
YesFreebearerView
4
Twilio API
Send SMS, make voice calls, video calls, and build complete communication solutions with Twilio's programmable APIs for messaging and voice.
YesPay as you gobasicView
5
Zoom API
Integrate Zoom's video conferencing, webinars, chat, and phone capabilities. Create meetings, manage users, access recordings, and build custom Zoom experiences.
YesFree (Zoom account required)oauth2View
6
Microsoft Teams API
Integrate Microsoft Teams collaboration features via Microsoft Graph API. Manage teams, channels, chats, meetings, and build Teams apps with tabs, bots, and message extensions.
YesFree (Microsoft 365 required)oauth2View
7
Slack API
Build apps and bots for Slack workspaces with APIs for messaging, notifications, workflows, and team collaboration features.
YesFreeoauth2View
8
Instagram API
Access Instagram's platform for publishing content, managing profiles, retrieving insights, and engaging with your audience programmatically.
YesFreeoauth2View
9
Twitter API (X API)
Access Twitter/X data including tweets, user profiles, trends, and real-time streams. Post tweets, search content, and build social media integrations.
YesFree (limited)oauth2View
10
Mailchimp API
Manage email campaigns, audiences, automation workflows, and marketing analytics with Mailchimp's comprehensive marketing platform API.
YesFree (500 contacts)api_keyView