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Paste your copy and a list of recipients, then read each personalized message as it will arrive. It catches {first_name} before it sends.

Your copy

Subject line

Body

Hi {{first_name}},

I was reading {{one_specific_thing}} and had one idea I think is worth ten minutes of your time.

Worth a short call next week?

Best,
Sam

Paste from Google Docs, Word or Notion. Bold, links and lists are kept. Write a merge tag as {{first_name}}.

Your list

Recipients, one per row, with a header row

Drop a .csv here, or paste rows. The list starts with sample data, made up.

Every message

company: 4 of 5. Uses the fallback in row 3
first_name: All 5 rows have a value
one_specific_thing: 4 of 5. Sends blank in row 4

5 messages2 blocked3 clean

What it checks in each message

Address: A missing or malformed address blocks that message.
Subject: An empty subject blocks it.
Empty merge fields: A field with no value and no fallback blocks the message, because it would send with a visible gap. Write {{company|your team}} and the fallback is used and the row is only counted.
Unresolved tags: A merge tag that did not resolve is flagged for a look.
Placeholder links: A link to example.com or to # is flagged.
Size: A message over 102 KB is flagged, because Gmail is reported to clip near that size. See the email size checker.

First-name fallbacks in 23 email tools

A fallback is what goes out when a row has no first name. Without one, most tools send a blank, and a few hold the email back. Each tool links to its own documentation, read in October 2026.

The first-name merge tag in each tool, how to give it a fallback, and what is sent when it is empty.
Tool	First-name tag	With a fallback	If it is empty
Email platforms
Mailchimp	`\|FNAME\|`	`\|IF:FNAME\|\|FNAME\|\|ELSE:\|there\|END:IF\|`A conditional merge tag. Or set a default merge tag value on the field, in Audience fields and merge tags.Our Mailchimp guide	A blank space
HubSpot	`{{contact.firstname}}`	Set a fallback value when inserting the token, or a default for the property under Settings, Marketing, Email, Personalization.Our HubSpot guide	Blank, if no default is set
Klaviyo	`{{ first_name }}`	`{{ first_name\|default:'there' }}`Our Klaviyo guide	Blank, so "Hey ,"
ActiveCampaign	`%FIRSTNAME%`	No fallback inside the tag. A default value is set on the contact field, under Contacts, Fields; check the First Name field accepts one.Our ActiveCampaign guide	A blank space
Brevo	`{{ contact.FIRSTNAME }}`	`{{ contact.FIRSTNAME\|default:"there" }}`	Not documented
Kit	`{{ subscriber.first_name }}`	`{{ subscriber.first_name \| strip \| default: "there" }}`Not in subject lines, where Kit does not run filters.	Nothing: the greeting reads Hello ,
Customer.io	`{{customer.first_name}}`	`{{customer.first_name \| default:"there"}}`On the latest Liquid version.	The message is not sent, and is logged as Failed
Salesforce Marketing Cloud	`%%First_Name%%`	`%%[Set @firstName = Trim(AttributeValue("First_Name")) Set @greeting = Iif(Empty(@firstName), "Hi there,", Concat("Hi ", @firstName, ","))]%%%%=v(@greeting)=%%`AMPscript, or a default value on the profile attribute. AttributeValue returns null when the field is missing, where reading the field directly can fail the send.Our Marketing Cloud guide	Blank
MailerLite	`{$name}`	`{$name\|default('there')}`	A blank space
Constant Contact	`[[FIRSTNAME]]`	`[[FIRSTNAME OR "there"]]`In custom-code emails; the editor has a Fallback field when you insert a contact detail.	Blank
Campaign Monitor	`[firstname,fallback=]`	`[firstname,fallback=there]`	A space: Hey , check out
Braze	`{{${first_name}}}`	`{{${first_name} \| default: 'there'}}`A value of only spaces does not count as empty.Our Braze guide	Blank
Iterable	`{{firstName}}`	`{{defaultIfEmpty firstName "there"}}`	Not documented
Marketo Engage	`{{lead.First Name}}`	`{{lead.First Name:default=there}}`Adobe documents a newer format for the Email Designer, {%=lead.city ?: "fallback" %}. Copy what the token picker inserts.Our Marketo Engage guide	Not documented
Salesforce Account Engagement (Pardot)	`{{Recipient.FirstName}}`	`{{#if Recipient.FirstName}}Hi {{Recipient.FirstName}},{{else}}Hi there,{{/if}}`Or set a Default Mail Merge Value on the field, under Account Engagement Settings, Configure Fields, Prospect Fields. A field default overrides the conditional.Our Pardot guide	Nothing is displayed
Oracle Eloqua	`<span class="eloquaemail">FirstName</span>`	No fallback inside the tag. Each field merge is a component (Assets, Components, Field Merge) with a default value, shown when the contact field is empty. The span holds the field merge's name.Our Eloqua guide	Not documented
Cold email tools
lemlist	`{{firstName}}`	`{{firstName\|there}}`	Nothing: Hello ,
Instantly	`{{firstName}}`	`{{firstName \| there}}`	Not documented
Smartlead	`{{first_name}}`	`{{#if first_name}} Hey {{first_name}}, {{else}} Hey there, {{/if}}`	Blank
Apollo	`{{contact.first_name}}`	`{{#if contact.first_name}}{{contact.first_name}}{{#else}}there{{#endif}}`	The email is held back and moved to Not sent
Outreach	`{{first_name}}`	`{{#if first_name}}{{first_name}} {{else}}there{{/if}}`	The step fails with Missing template variable
Mail merge from a spreadsheet
Gmail mail merge	`@firstname`	No fallback inside the tag. Gmail flags the missing value before sending and asks for a default.	An error before anything is sent
Mailmeteor	`{{ firstname }}`	`{{ firstname \| there }}`	A blank space

A tag goes out as typed, braces and all, only when the tool does not recognize it: mistyped, or written in another tool’s format. Mailchimp and lemlist both say so. That is the email that arrives saying Hi {first_name}.

Mail-merge preview

Your copy

Your list

Every message

What it checks in each message

First-name fallbacks in 23 email tools

Further reading

Who do you want to hear back from?

Mail-merge preview