Mailerflow AI Email Builder: How It Works

The Mailerflow AI email builder is a feature inside Mailerflow's campaign flow: you describe the email you want in plain language, and it returns a complete responsive design plus subject lines and preview text. You then edit the result in the visual block editor and send it from your own verified domain. There is no separate app to install and no plugin to connect — the builder sits where you already write and schedule campaigns.

What the Mailerflow AI email builder actually does

The tool takes a written description and produces three things at once: a responsive, block-based email layout; a set of subject line options; and preview text. The output is a draft, not a finished send. It lands in the visual block editor, where you can rearrange blocks, rewrite copy, swap images and adjust anything else before the campaign goes out.

It is not a standalone design tool, and it does not send anything on its own. It is a generation step inside the normal campaign workflow — the same place you would otherwise start from a blank template or a reusable one. Generated emails can be saved as templates, so a layout you like becomes a starting point for the next campaign.

The same plain-language approach also powers the AI automation builder: describe a workflow in a sentence, and Mailerflow drafts it — trigger, waits, conditions and emails — for review before activation.

How it works: from description to reviewed send

1. You write the description. At minimum, cover the goal of the email, who it is going to, the offer or news, the tone you want, and any fixed elements such as a discount code, a date or a required link. The more specific the description, the less editing the draft needs.

2. The builder generates the draft. You get a responsive design built from blocks — headings, heroes, products, columns, social links — along with subject line options and preview text.

3. The draft opens in the visual block editor. This is where the real work happens. You are editing a structured email, not a flat image, so blocks can be reordered, duplicated or removed without breaking the layout.

4. You review before anything is sent. Subject line, preview text, links, merge fields, mobile rendering, offer details, audience and sending domain all get checked at this stage.

5. You schedule or send. Scheduling is available per campaign, and inside automations you can use "send when the contact is most active" instead of a fixed time.

Writing a description that produces a usable first draft

A weak prompt produces a generic layout that takes longer to fix than to build from scratch. A specific prompt produces something close to finished.

Weak: "Write a newsletter about our new feature."

Stronger: "Launch email for existing customers on the Pro plan. Announce the new shared inbox feature. Tone: direct, no hype. Include a hero image, one short paragraph on what changed, a three-item benefit list, and a single CTA button reading 'Try shared inbox' linking to /features/shared-inbox. Mention that the feature is included in their current plan at no extra cost. Sign off from the product team."

The second version names the audience, the single job of the email, the structure, the CTA text and the destination. Those are exactly the details the builder cannot guess, and they are the ones you would otherwise fix by hand.

Reviewing the generated email before you send

AI output is a first draft, so the review is where quality is decided. Check these specifically:

• Subject line versus body. Does the promise in the subject actually appear in the email? An overpromising subject line can hurt an AI-assisted campaign.
• Preview text. It should extend the subject line, not repeat it. If both say the same thing, rewrite one.
• Links and merge fields. Confirm every link resolves and every personalization field has a sensible fallback.
• Mobile rendering. Generated layouts are responsive by default, but long headings and wide product blocks still need a look on a narrow screen.
• Offer details and dates. Codes, deadlines and prices are the details most likely to be wrong in a generated draft.
• Audience and sending domain. Confirm the segment is the one you meant and that the campaign sends from your verified domain.

It also helps to decide up front what you will measure. Mailerflow shows analytics for delivery, bounces, complaints, clicks and approximate opens, per campaign and overall, so the review can include a simple question: what would make this send a success?

Where the AI builder fits in a real campaign

A typical campaign looks like this:

1. Build the audience. Dynamic segments can be based on fields, tags, engagement, events and website behavior, and AI segmentation can turn a plain-language description into a segment.
2. Generate the email with the AI builder, then edit it in the block editor.
3. Optionally A/B test subject lines or content variants.
4. Schedule the send, or place the email inside an automation with waits, conditions, webhooks and AI steps.
5. Review results in analytics and feed what you learn into the next campaign.

Two related capabilities are worth knowing about because they change what you can put in the email. AI personalization steps and website-behavior data collected through the JS SDK let you tailor content to what a contact has read or done, rather than only to what you know from a form field. If you are planning a sequence rather than a single send, the automation builder drafts the whole flow from a sentence, which pairs naturally with the email builder.

Two worked examples

Both examples below are illustrative, written to show the shape of the workflow rather than results.

Example 1: product launch to an existing segment. Description: "Announce the new reporting dashboard to customers who logged in during the last 30 days. Tone: confident and brief. Hero image, one paragraph on what the dashboard shows, three bullet benefits, CTA 'See your dashboard' linking to /app/reports. No discount." The builder returns a hero block, a text block, a three-item list, a CTA button and a set of subject lines. The human edits: tightens the opening paragraph, swaps the hero image for a current screenshot, picks the subject line that names the feature, and writes preview text that adds a detail the subject does not carry.

Example 2: win-back email for inactive contacts. Description: "Win-back email for contacts who have not opened or clicked in 90 days. Acknowledge the silence without guilt-tripping. One clear reason to come back: the new digest format. CTA 'See what's new' linking to /digest. Include an unsubscribe link prominently." The builder returns a short layout with a single CTA. The human edits: shortens the body further, checks that the segment excludes recent purchasers, and confirms the sending domain is the one with the best reputation for this audience.

Common mistakes with AI-generated emails

• Sending the first draft. The draft is a starting point. Fix: set aside time to edit each email before sending.
• Letting the subject line overpromise. Fix: read the subject, then read the body, and confirm they match.
• Leaving placeholder links or merge fields. Fix: click every link in preview and test the merge fields with a real contact record.
• Skipping the mobile check. Fix: preview on a narrow viewport before scheduling.
• Sending to the wrong segment. Fix: open the segment and check the count and the rules before you schedule.
• Sending before the domain is set up. Fix: complete the guided DKIM, SPF and DMARC setup and wait for automatic verification before your first campaign.
• Treating AI output as a substitute for a clear offer. Fix: decide what the email is asking for before you write the description.

Quick checklist before you hit send

• The description named the audience, the goal and the CTA destination.
• The subject line and preview text say different, complementary things.
• Every link resolves and every merge field has a fallback.
• The email renders correctly on a narrow screen.
• Offer details, codes and dates are accurate.
• The segment is the one you intended, and suppressions are in place.
• The sending domain is verified and reputation monitoring is active.
• You have decided whether to A/B test, and what the variant is.
• You know which metric will tell you whether this worked.

FAQ

Do I need design skills to use it? No. You describe the email and edit a block-based layout. Knowing what a good email looks like helps more than knowing how to build one.

Can I edit what the AI generates? Yes. The output lands in the visual block editor, where every block, line of copy and image can be changed, reordered or removed.

Does it write subject lines too? Yes — the builder returns subject line options and preview text alongside the design.

Can it build automations as well as single emails? Yes. The AI automation builder drafts a workflow from a sentence — trigger, waits, conditions and emails — for you to review before activation.

How many AI actions do I get? It depends on the plan: Free includes 100 AI actions per month, Starter 500, Growth 2,500, Pro 5,000, Business 10,000 and Scale 30,000. Check the official pricing page for current details.

Is my data hosted in Europe? Yes, Mailerflow data is hosted in Europe, and the platform includes GDPR tools such as data export, erasure, consent logs and configurable retention.

Plans and AI action limits

Plan details below are the current published figures; confirm them on the official pricing page before you decide.

Every paid plan includes unlimited emails, and yearly billing costs the same as 10 months. The Free plan carries Mailerflow branding in emails; paid plans do not. Higher tiers also raise sending domains, users and active automations, which matters if you run several brands or a large sequence library.

If you are evaluating the builder specifically, the fastest way to judge it is to write one real description for a campaign you already have planned and see how close the first draft lands. The AI email builder page has the details, and you can start on the free plan without a credit card.

Describe your next email or automation in one sentence and let Mailerflow's AI build it — free plan, no credit card.