Customer.io vs. Braze: How to compare platforms as you scale 

The question behind every platform comparison comes down to which platform helps you do your best work and hit your biggest goals. For most marketers, that means a platform your team can set up quickly, build in every day without waiting on engineering, and keep growing on as audiences, channels, and data expand. Ease of setup, day-to-day usability, and room to grow all carry weight, and you can test each one before you sign.

Room to grow is the part you can check against production numbers, and Customer.io's 9,000+ customers put it to the test every day. Customer.io sent more than 100 billion messages in 2025, and in a 30-day window, its workspaces process up to 7.5 billion events, about 250 million a day. Customers send up to 395 million messages in 30 days across email, push, and webhooks, ten customers each send more than 60 million emails a month, accounts manage up to 160 million profiles, and during Black Friday and Cyber Monday about 92% of messages completed in under one second.

Reliability at that volume is the baseline. The rest of your decision comes down to what the platform is like to work with every day. Can your team use every event and attribute you collect in segments and journeys? Will your bill be easy to forecast as your audience grows? How quickly can you go from a signed contract to a live journey?

We built a five-question framework to help with your own evaluation of Customer.io and Braze, covering event volume, send throughput, data model flexibility, cost structure, and time to launch. Here's how Customer.io answers each one, so you can put the same questions to Braze and compare the two for your team.

• Customer.io workspaces process up to 7.5 billion events in 30 days (about 250 million a day) and ingest more than 35,000 events per second at peak, and accounts manage up to 160 million profiles.
• Observed peaks for a single customer in production reached more than 13,500 emails per second and nearly 24,000 push notifications per second, and some of our largest customers each send more than 60 million emails a month.
• During Black Friday and Cyber Monday, about 92% of messages sent through Customer.io completed in under one second, and about 97% within three seconds.
• Customer.io doesn't cap data points, offers unlimited monthly API calls on every plan, and keeps event properties usable in segments and journeys beyond a 30-day window.
• G2's Fall 2026 reports ranked Customer.io #1 in the Momentum Grid for both Marketing Automation and Personalization, ahead of Braze in both, with Leader badges in Marketing Automation, Mid-Market, and Small-Business, and #7 in the Global Marketing Automation Grid.

For each of the five areas below, you'll find the question to ask any vendor and how Customer.io performs.

How many events does one production workspace process per day, and is event data capped or limited by a lookback window?

Workspaces process up to 7.5 billion events in 30 days, about 250 million a day, and ingest more than 35,000 events per second at peak. Monthly API calls are unlimited on every plan, with no data point caps, and event properties stay usable in segments and journeys beyond a 30-day window.

What are your observed peak sends per second by channel, and what do your largest customers send in a month?

Observed peaks for a single customer: more than 13,500 emails, nearly 24,000 push notifications, more than 6,400 webhooks, more than 2,800 in-app messages, and more than 2,300 SMS messages per second. Ten customers each send more than 60 million emails a month, and customers send up to 395 million messages in 30 days across email, push, and webhooks.

Can you model accounts, subscriptions, and other non-person data, identify people by more than one ID, and sync with your warehouse and CRM?

Custom objects (two object types on Essentials, ten on Premium, custom on Enterprise), nested event data, workspaces that identify people by ID, email, or both, reverse ETL on every plan, and Salesforce data in and data out.

What drives your bill as volume grows, and what does the base price include?

Pricing is built on profiles and email volume. Plans start at $100 a month for Essentials and $1,000 a month for Premium, with custom Enterprise pricing. Push notifications, in-app messages, webhooks, and API calls are unlimited.

Your AI Agent, which can build an automation from a single prompt, and LLM actions, which bring AI into the steps of an automation, are included on every plan from your free trial through Enterprise, with additional AI credits available as usage grows.

How long does it take to go from contract to a first live journey, and what onboarding and migration help comes with the plan?

A self-serve free trial lets you build before you buy, and Premium and Enterprise plans offer onboarding support (90 days on Premium), migration support, and a dedicated technical implementation specialist.

G2 named Customer.io Most Implementable in Small-Business, the segment's highest Implementation rating, which measures how quickly and smoothly teams get up and running.

Teams that choose Customer.io over Braze cite five reasons most often:

1. A flexible data model
2. Two-way data connections
3. Costs they can forecast
4. An open approach to AI
5. Hands-on support from day one

Customer.io doesn't cap data points, so every event, attribute, and object you send stays available for segments, triggers, and personalization. Monthly API calls and people attributes are unlimited on every plan, and event properties remain usable in segments and journeys beyond a 30-day window, so a team can build a re-engagement segment on last quarter's behavior without planning for it when the event first fired.

Custom objects go beyond individual people. A B2B SaaS team can model accounts, subscriptions, and workspaces as objects connected to the people inside them, then use object attributes and nested event data in conditions and personalization. Essentials includes two object types, Premium includes ten, and Enterprise is custom. Workspaces can also identify people by ID, email, or both, which fits teams with anonymous-to-known transitions and email-first sign-ups.

Customer.io supports first-party Salesforce data in and data out, mapping contacts, leads, accounts, and opportunities to profiles, events, custom objects, and relationships. Reverse ETL is included on every plan, and data warehouse destinations come with Premium and Enterprise, so the data your team already trusts reaches your messages and flows back out to the tools that need it.

Customer.io pricing is built on profiles and email volume, two numbers you already track. Push notifications, in-app messages, webhooks, and API calls are unlimited, additional email costs $0.12 per 1,000, and your AI Agent and LLM actions are included on every plan. That makes it straightforward to model your bill at your current volume and at double.

Your AI Agent builds from a single prompt. Describe the automation or segment you want, and the Agent creates it, drafts the messages, and analyzes how it performs, while respecting user permissions and asking for approval on sensitive actions. LLM actions bring AI into the steps of an automation, saving structured output as journey attributes you can use for personalization and conditions, and Routines run recurring tasks such as deliverability checks and segment audits on a schedule.

For teams that work in other AI tools, the Customer.io MCP server connects Claude, ChatGPT, and Cursor to your workspace, and admins decide whether MCP connections can modify live resources or see sensitive profile data, with both settings off by default. The Customer.io CLI is built for AI agents and coding assistants as well.

A self-serve free trial lets you build in the platform before you commit. Premium and Enterprise plans add chat support, a two-hour first outreach response time, and onboarding support, and a dedicated customer success manager and technical implementation specialist are available. G2 awarded Customer.io Best Relationship in Mid-Market, the segment's highest rating for support quality and ease of doing business.

Customer.io workspaces process up to 7.5 billion events in 30 days and ingest more than 35,000 events per second at peak, while accounts manage up to 160 million profiles.

On the send side, the observed peaks for a single customer in production were more than 13,500 emails per second, nearly 24,000 push notifications per second, more than 6,400 outbound webhooks per second, more than 2,800 in-app messages per second, and more than 2,300 SMS messages per second. Customer.io's largest email sender delivered more than 254 million emails in 30 days, and its largest push sender delivered more than 288 million push notifications in the same period.

Every throughput figure here is an observed peak for a single customer in production, measured at one-second resolution between August and September 2026. These figures describe what the platform has delivered under real traffic and are not capacity limits.

Peak season gives the clearest picture of delivery speed. During Black Friday and Cyber Monday, about 92% of messages sent through Customer.io completed in under one second, and about 97% completed within three seconds. Across the year, the platform runs at 99.98% infrastructure uptime and sent more than 100 billion messages in 2025.

Teams at Notion, Lovable, and Figma trust Customer.io to manage their customer engagement programs for millions of users around the world. Notion's lifecycle team, for example, runs localized onboarding for a user base where 80% of users live outside the United States, and its localized campaigns lifted conversion by 6-7% with open rates of 49-51%.

Customer.io doesn't cap data points, so every event, attribute, and object you send stays available for segments, triggers, and personalization. Monthly API calls and people attributes are unlimited on every plan, and event properties remain usable in segments and journeys beyond a 30-day window, which lets a team build a re-engagement segment on behavior from last quarter without planning for it when the event first fired.

Custom objects extend that flexibility beyond individual people. A B2B SaaS team can model accounts, subscriptions, and workspaces as objects connected to the people inside them, then use object attributes and nested event data in conditions and personalization. Essentials includes two object types, Premium includes ten, and Enterprise is custom.

Identity follows the same pattern. Customer.io workspaces can identify people by ID, email, or both, which fits teams with anonymous-to-known transitions and email-first sign-ups. On the integration side, reverse ETL is included on every plan, data warehouse destinations come with Premium and Enterprise, and Customer.io supports Salesforce data in and data out, mapping records to profiles, events, and custom objects. The Data & Integrations page covers the full list.

See how Customer.io works for your business. Book a demo and bring your peak volume, your biggest goals, and your current Braze quote, and we'll show you how Customer.io handles each one. Prefer to test it yourself? Start a free trial and build your first journey today.

No. Customer.io serves startups, mid-market teams, and enterprise senders, with plans and support that change as volume grows.

Customer.io loves startups, too. Early-stage companies that have raised under $10M can get 12 months of Customer.io free through the Startup Program.

Yes. Customer.io handles event volumes at the scale of billions per month in production: workspaces process up to 7.5 billion events in 30 days, about 250 million a day, and ingest more than 35,000 events per second at peak. Monthly API calls are unlimited on every plan.

Customer.io pricing is built on profiles and email volume, with unlimited push notifications, in-app messages, webhooks, and API calls, and with your AI Agent and LLM actions included on every plan. Pricing for any platform at scale depends on your profile count, channel mix, data volume, AI usage, support tier, and onboarding needs, so the most accurate comparison is a quote from each vendor on the same volumes. Book a demo to get a Customer.io quote on yours.

Timelines depend on how many journeys, data sources, and channels you migrate. Premium and Enterprise plans offer onboarding support, migration support, and a dedicated technical implementation specialist, and Premium includes 90 days of onboarding support.

Yes. Customer.io supports GDPR, CCPA, HIPAA, SOC 2 Type II, and ISO 27001 requirements, with SSO, two-factor authentication, role-based permissions, and US and EU data centers. HIPAA compliance and audit logging are available on Premium and Enterprise plans by arrangement.