Store any data. Personalize everything.
Go beyond basic contact info. With SMASHSEND Custom Fields, track any data that matters to your business — from shoe sizes to subscription tiers, purchase history to preferences.
Unlimited custom fields · All data types supported · API access included
favorite_categories["Electronics", "Fashion"]lifetime_value$2,450.00last_purchase_date2024-03-15preferred_sizeLargeapi_calls_this_month45,291team_members12storage_used_gb28.5feature_adoption_score87%The most flexible custom fields in email marketing
While others limit you to basic fields, SMASHSEND gives you the power to store any data type, create complex properties, and use them everywhere.
∞
Unlimited fields
10+
Data types
0ms
Real-time sync
Every data type you need
Text & numbers
Store names, descriptions, IDs, scores, prices, quantities, or any text and numeric data. Perfect for basic customer information and metrics.
Lists & arrays
Track multiple values like product interests, tags, categories, or preferences. Use single-select or multi-select options for structured data.
Dates & booleans
Capture timestamps, anniversaries, expiration dates, or yes/no flags. Perfect for time-based automations and conditional logic.
JSON objects
Store complex nested data structures for advanced use cases. Perfect for developers who need maximum flexibility.
Encrypted fields
Store sensitive data securely with field-level encryption. Perfect for PII, tokens, or any confidential information.
Computed fields
Create dynamic fields that calculate values based on other properties. Update automatically as source data changes.
Use custom fields everywhere
Your custom fields aren't locked away — use them across the entire SMASHSEND platform for truly personalized experiences.
In email campaigns
Personalize every email with custom field tokens. Display customer-specific data, recommendations, or dynamic content based on any property.
In segmentation
Build powerful segments using any custom field. Combine multiple conditions with AND/OR logic to target exactly the right audience.
In automations
Trigger workflows based on custom field changes. Update fields automatically, create conditional branches, or sync with external systems.
Via API & webhooks
Full API access to read and write custom fields. Receive webhooks when fields change. Keep your entire stack in sync.
Personalize with field tokens
Reference any property directly in your campaign copy.
Hi ,
Based on your preference for ,
we thought you'd love our new collection!
Your loyalty points:
Member since: Real-world use cases
See how businesses use SMASHSEND Custom Fields to create powerful, data-driven email experiences.
E-commerce
Personalization that uses real history
Track purchase history, browsing behavior, size preferences, and wish list items, then target recommendations off those fields.
Targeted product recommendations convert 3x better.
SaaS
Onboarding driven by adoption
Monitor feature adoption, usage metrics, and subscription details, and trigger onboarding emails from user behavior and progress.
Every onboarding email matches where the user actually is.
Education
Courses that respond to progress
Track course progress, quiz scores, and learning preferences to send content recommendations and achievement celebrations.
Learners get the next step, not the same newsletter.
Healthcare
Compliant, personal reminders
Store appointment history, preferences, and consent data securely with field-level encryption.
HIPAA-compliant reminders and personalized health tips.
Real estate
Match leads to listings
Track property preferences, budget ranges, and viewing history so the right listing reaches the right lead.
Leads matched with properties automatically.
Gaming
Player-aware messaging
Store player stats, achievements, and preferences to drive game updates, rewards, and recommendations.
Updates that reflect how each player actually plays.
SMASHSEND vs. limited field systems
Most email platforms limit you to basic fields. See why developers and marketers choose SMASHSEND for true flexibility.
Developer-friendly integration
Built by developers, for developers. Integrate custom fields with your application in minutes, not days.
// Create a custom field
const field = await smashsend.customFields.create({
name: 'subscription_tier',
type: 'select',
options: ['free', 'pro', 'enterprise'],
defaultValue: 'free'
});
// Update contact with custom field
await smashsend.contacts.update('ctc_abc123', {
email: 'user@example.com',
properties: {
subscription_tier: 'pro',
last_login: new Date(),
feature_flags: ['dark_mode', 'beta_access'],
usage_stats: {
api_calls: 1523,
storage_gb: 12.5
}
}
});Part of the complete SMASHSEND platform
Custom fields work seamlessly with every SMASHSEND feature. One platform, infinite possibilities.
Start building with custom fields today
Join thousands of businesses using SMASHSEND Custom Fields to create truly personalized email experiences.
Unlimited fields • All data types • Full API access • Free forever