Knock is developer-first messaging infrastructure that provides APIs and SDKs for engineering teams to build custom notification systems. Marketo is a B2B marketing automation platform that supports email, push, and SMS, but channel control and workflow features are limited and basic compared to developer-focused tools.

Knock focuses on transactional product notifications and in-app messaging with full programmatic control and advanced orchestration. Marketo specializes in B2B campaign orchestration for large marketing teams, with less flexibility for complex, event-driven notification logic.

While Marketo can send messages across email, push, and SMS, it's built for marketing campaigns rather than transactional notifications. Control is limited and features are basic; developers often find the workflow builder restrictive for complex notification logic.

Knock provides full programmatic control through APIs and code-based workflows, plus advanced features like batching and throttling, designed for transactional product and customer messaging.

Knock excels at product and customer messaging use cases like user onboarding flows, activity notifications, system alerts, and other product-driven communications.

However, features like Broadcasts and Guides enable engineering, product, and growth teams to work collaboratively to send relevant lifecycle messaging and one-off promotional emails, similar to Marketo's campaign capabilities.

Unlike Marketo, which prioritizes ease of use for marketing teams, Knock is purpose-built for developers, so initial setup requires some technical involvement.

From there, non-technical users can easily create messaging workflows, manage notification templates, edit and send one-time messages, ship in-app messaging, and view analytics without any developer involvement.

Marketo offers B2B marketing analytics for campaign performance, lead scoring, and attribution across its channels. Knock provides extensive engagement analytics across channels plus end-to-end observability—API logs, message debugging, and delivery tracking—giving developers full visibility into notification flows.

Knock is built as infrastructure to handle billions of notifications with guaranteed delivery and idempotency. Marketo can handle large volumes across its channels but is optimized for scheduled marketing campaigns; its basic workflow features and limited control make it a poor fit for real-time, event-driven notifications at scale.

Marketo supports sending email, push, and SMS messages, but channel features and control are basic within the platform. Knock supports the same channels and more, including in-app notifications and chat apps like Slack, Microsoft Teams, and WhatsApp.

Knock offers greater integration flexibility, integrating with 25+ messaging providers so teams can choose which providers they want to use, such as Amazon SES for transactional email, Resend for promotional email, and Twilio for SMS notifications.

Yes, some companies use both. Engineering teams often use Knock for transactional messaging (alerts, updates, collaboration messages) and messaging workflows requiring advanced orchestration, while marketing teams use Marketo for email marketing campaigns.

However, this separation can lead to inconsistent messaging over time, and using two systems costs far more than just using Knock to handle all marketing and customer messaging.

Knock typically offers more cost-effective pricing for engineering teams building notification systems. While Marketo requires enterprise-tier subscriptions and is often sold as part of Adobe's marketing cloud, Knock provides transparent usage-based pricing starting at $0 for the first 10,000 notifications, making it accessible for startups and growing companies, with volume discounts for larger enterprise organizations.

All plans include unlimited data ingestion and unlimited channels with no onboarding or service fees, and overages are only incurred by volume of sent messages.

Both platforms offer enterprise compliance features. Knock provides SOC 2 Type 2 certification and supports GDPR/CCPA requirements. Marketo (as part of Adobe) offers similar compliance but typically requires enterprise contracts.

Knock's infrastructure approach gives engineering teams more control over data handling.

Knock is designed for rapid implementation by developers, with most teams shipping notifications within hours using pre-built components and full API control. Marketo typically requires weeks or months of setup and training; its visual interface and basic workflow features offer less flexibility for developers who need fine-grained control.

If your engineering team needs to ship quickly, Knock's developer experience provides faster time-to-value.

Most engineering teams migrate from Marketo to Knock within 2-4 weeks, depending on notification complexity. Knock's responsive support team help accelerate the process.

The investment pays off quickly through improved developer productivity and reduced maintenance.