Which API Should I Use?
Meet the two ways to send messages on Kudosity. Both run on the same platform and share your account, API keys, senders, reporting, and billing — so you can pick what fits your build today and evolve later.

Quick Recommendation
TransmitMessage (V2)
Recommended for new builds
Modern API with MMS, WhatsApp, RCS support and API-managed webhooks.
TransmitSMS (V1)
For classic integrations
Fully supported with multi-recipient sends and custom tracked links.
API Comparison
Choose TransmitMessage (V2) when you need:
- MMS via API (send & receive) - V2 is the only API with MMS support, including an
inbound_mms
webhook - Simple, programmatic sends with modern webhooks - Webhooks are created/managed by API; JSON responses; streamlined API-key auth
- WhatsApp (send & receive) - Rich WhatsApp messaging, notifications
- RCS (send & receive) - RCS notifications, rich messaging
- Track multiple links in one SMS - Auto-detect & track multiple links in a message
- Your own message reference alongside our message ID - Add a
message_ref
for reconciliation/workflows
💡 Recommendation: Start on V2. Keep V1 if you rely on multi-recipient requests or custom tracked links. You can use both under the same account and senders.
Feature Comparison
Account & Authentication
- Unified account & UI: Same login, senders, reporting, and billing across both APIs
- Auth: V2 uses API-key auth; V1 uses Basic Auth (key + secret)
Webhooks & Delivery
- Webhooks: V2 webhooks are managed via API (create/list/update/delete). V1 webhooks are configured in the UI
- Delivery reports: V2 via webhook; V1 via webhook or email
- Retries: Both retry failed webhook deliveries; V2 has a more granular schedule
Message Features
- Message Types: V2 supports SMS, MMS, WhatsApp, RCS; V1 supports SMS only
- Link Tracking: V2 auto-detects multiple links; V1 supports custom domains
- Multi-recipient: V1 supports batch sends; V2 requires individual requests
- Response Format: V2 is JSON-only; V1 supports both JSON and XML