Character Counting

Templates automatically calculate SMS segments to help you estimate costs.

Automatic Calculation

Code
 
import { getTemplate, renderTemplate } from '@relay-works/templates';

const template = getTemplate('order-confirmed');
const result = renderTemplate(template, {
  company: 'Acme Store',
  orderNumber: 'A1B2C3',
  itemCount: 3,
  amount: '49.99',
  url: 'https://relay.link/order-123'
});

console.log(`Message: ${result.text}`);
console.log(`Characters: ${result.characterCount}`);
console.log(`Segments: ${result.segments}`);
console.log(`Encoding: ${result.encoding}`);
console.log(`Cost estimate: $${result.segments * 0.02}`);

Render Result

Every template render returns:

Code
 
{
  text: string;           // The rendered message
  characterCount: number; // Total character count
  segments: number;       // Number of SMS segments
  encoding: string;       // 'GSM-7' or 'UCS-2'
}

SMS Segment Limits

GSM-7 Encoding

• Single segment: 160 characters
• Multi-segment: 153 characters per segment

UCS-2 Encoding (Unicode)

• Single segment: 70 characters
• Multi-segment: 67 characters per segment

Cost Calculation

With Relay's pricing at $0.02 per segment:

Code
 
const result = renderTemplate(template, data);
const cost = result.segments * 0.02;

console.log(`This message will cost $${cost.toFixed(2)}`);

Optimizing for Segments

Keep messages under 160 characters for single-segment delivery:

Code
 
// Check before sending
if (result.segments > 1) {
  console.warn('Message requires multiple segments');
  console.log('Consider shortening URLs or company names');
}

URL Shortening Impact

Long URLs can increase segment count:

Code
 
// ❌ Long URL - 2 segments
const longResult = renderTemplate(template, {
  company: 'Acme',
  url: 'https://mystore.com/orders/a1b2c3/tracking?utm_source=sms'
});
console.log(longResult.segments); // 2

// ✅ Short URL - 1 segment
const shortResult = renderTemplate(template, {
  company: 'Acme',
  url: 'https://relay.link/ord-123'
});
console.log(shortResult.segments); // 1

Next Steps:

• Compliance Features
• TypeScript Support
• Best Practices