For Marketo teams

The Marketo email builder without the syntax.

Modular Mail is an email CMS. Your templates are configured with locked modules and editable content fields. Marketers (yours or your client's) build campaigns by filling in those fields. No mktoModule syntax, no broken layouts. Export clean HTML to Marketo in one click.

The challenge

The Marketo email problem

Marketo is great for automation, deliverability, and reporting. Building email content in it is the hard part. Here's what teams actually deal with day-to-day.

The classic editor is being retired

Adobe's new Email Designer is rolling out and migration is forced. The new editor has gaps: limited brand guardrails, no custom webfont support without manual CSS injection, content locking that doesn't fully prevent style changes. Most teams are unsure what the right path forward is.

Template syntax is a developer bottleneck

mktoModule, mktoText, mktoImg, and variable syntax all need a developer who knows them. Every module change means a dev ticket. Developers fluent in HTML email and Marketo syntax are rare; the bottleneck is real.

Design Studio has limitations

Storing and managing templates in Design Studio is clunky. No visual preview of modules, no drag-and-drop at the template level in classic, manual version control. Teams accumulate dozens of variations with no clean way to manage them.

Brand consistency drifts

Even with modules, the editor gives users enough rope to break layouts. Rich-text fields let people change fonts, colours, and spacing in ways that drift from the brand. The more campaigns you ship, the worse the drift.

You're locked into one platform

Templates built with Marketo syntax only work in Marketo. Migrate ESPs and you start from scratch. An ESP-agnostic approach avoids this entirely.

The new editor mangles your HTML

Upload clean HTML to the new Email Designer and it runs through an undocumented conversion: inline styles change, structure shifts, rendering breaks. There's no documentation explaining what the converter does. Teams end up reverse-engineering the editor instead of building emails.

How it works

Modular Mail alongside Marketo

Set up the template system once. Your team manages the content from there. Marketo handles the sending.

1. Templates configured for your Marketo team

We configure the template structure for you, or your own developer or agency can do it. Modules are locked. Marketers can't break the layout, change fonts, or mess with spacing. Content fields are defined: text, images, links, CTAs.

  • No Marketo template syntax needed; templates are plain HTML with mm-editable tags
  • Bring existing Marketo templates, Figma files, or brand guidelines
  • Configured and handed to your team, ready to use
Template conversion service →
Modular Mail template builder showing editable regions inside email modules

2. Marketing builds campaigns

Marketers pick modules, fill in fields, reorder, preview on desktop and mobile. They see content fields, not code. Content management, not code editing.

  • Content fields only, no code visible
  • Drag-and-drop module reordering
  • AI Copy Assistant for text fields
  • AI Alt Text for accessibility
  • Live desktop and mobile preview

3. Export to Marketo

One click, clean HTML, ready to upload to Marketo Design Studio. Add tokens and dynamic content there, then send. The same HTML works with any other ESP, too.

  • One-click HTML export
  • Clean code Marketo accepts without issues
  • No Marketo-specific syntax in the output
  • Send tests to Litmus or Email on Acid before uploading
HTML export panel showing clean output ready for Marketo
The workflow

Where Modular Mail fits

Design
01

Design

Figma, brand guidelines, or existing Marketo templates

Modular Mail
02

Set up templates

Developer defines modules and content fields. One-time setup.

03

Build campaigns

Marketer fills in text, images, links. Drag-and-drop modules.

04

Export HTML

One-click export. Clean, standards-compliant HTML.

Marketo
05

Send from Marketo

Upload to Design Studio. Add tokens, dynamic content. Send.

Why teams switch

The reasons we hear most often

From in-house teams trying to escape the new Email Designer to agencies handing off to clients without teaching them Marketo.

The classic editor is being retired

Adobe is rolling out the new Email Designer. Rather than rebuild everything for it, teams move template management to Modular Mail and export HTML to Marketo for sending.

No dev time available for email

Every new module or template tweak needs a developer who knows Marketo syntax. With Modular Mail, setup happens once and marketers handle everything after that.

Marketers keep breaking templates

Marketo's content locking is incomplete. In Modular Mail, the editor literally cannot reach the HTML. Only content fields. No broken layouts, no off-brand styling.

Send from other platforms too

Templates built in Modular Mail are clean, portable HTML. Use the same templates in Marketo, HubSpot, Salesforce, anywhere. One template system, no platform-specific syntax.

Building email systems for clients

If you're an agency setting up templates for a client's marketing team, Modular Mail gives you a clean handoff. Lock the structure, hand them an editor they can't break, no Marketo syntax required.

Brand consistency at scale

Modules and tokens are the only options. Buttons stay on-brand. Headings stay on-brand. Spacing stays on-brand. Marketing volume goes up without quality going down.

Comparison

Marketo's editor versus Marketo + Modular Mail

A factual comparison. Marketo handles automation and sending. Modular Mail handles template management and campaign building.

Feature Marketo Email Editor Marketo + Modular Mail Recommended
Template setup Marketo template syntax (mktoModule, mktoText, etc.) Standard HTML with mm-editable tags
HTML import behaviour New editor rewrites uploaded HTML in undocumented ways Export clean HTML; Marketo accepts it without conversion issues
Who can build campaigns Anyone, but risk of breaking layouts Anyone. Structure is locked, content is editable
Brand guardrails Limited content locking, incomplete in new editor Full lockdown. Marketers only see content fields
Module management Inside Design Studio or the new editor Visual module library with drag-and-drop
ESP portability Marketo-only syntax Export clean HTML to any ESP
Custom fonts Manual CSS injection in new editor Defined in template setup, applied automatically
AI assistance Not available in the email editor AI Copy Assistant and AI Alt Text built in
Preview and testing Basic preview; need Litmus or EoA for real testing Built-in desktop and mobile preview, plus Litmus / EoA integration
We used to wait three to five days for dev to update our email templates. Now my team builds campaigns in an afternoon. Same custom designs, zero technical dependency.
Hin Shah Head of CRM · Dr. Barbara Sturm
FAQ

Modular Mail with Marketo, in detail

  1. Can I use my existing Marketo email templates with Modular Mail?
    Yes. Your existing HTML can be converted into Modular Mail's module system. You or your developer strips out the Marketo-specific syntax and adds mm-editable tags. We also offer professional template conversion as a service.
  2. Does Modular Mail integrate directly with Marketo?
    No, and that's intentional. Modular Mail is ESP-agnostic. You build campaigns in our editor and export clean HTML, then upload to Marketo. No API integration to maintain; no platform lock-in.
  3. What happens to my Marketo templates if I use Modular Mail?
    They keep working. Modular Mail sits alongside Marketo: it handles content management and campaign building; Marketo handles sending, automation, and reporting. Think of it as replacing Design Studio for email creation, not Marketo itself.
  4. Do I still need Marketo template syntax?
    No. Modular Mail templates use standard HTML with simple mm-editable attributes. The exported HTML is clean, with no platform-specific syntax. Works in Marketo and any other ESP.
  5. How long does it take to set up?
    If you have existing templates, conversion typically takes a few days depending on complexity. If you need templates built from scratch, scope depends on the design work. We scope upfront so there are no surprises.
  6. I'm an agency building for a client. Does this workflow work for me?
    Yes. Many of our users are agencies building template systems for client marketing teams. You set up the modules and content fields; your client builds campaigns and exports HTML to Marketo. You stay involved for new modules; the client owns the day-to-day.
  7. Is Modular Mail a replacement for Marketo?
    No. Modular Mail replaces the template-building and campaign-content workflow. You still use Marketo for sending, automation, analytics, and lead scoring. Read more about the email CMS approach.
Get started

Simplify your Marketo email workflow.

See how Modular Mail works with your existing Marketo templates. Or let us convert them for you.