DLT Template Format Validator
Paste your SMS template and check it against common DLT formatting rules before submitting it for registration: variable syntax, length, and disallowed patterns.
Common reasons DLT templates get rejected
Most rejections come down to formatting, not content: a missing variable bracket, an unregistered URL in a service-implicit template, or a template that doesn't match its declared category. Catching these before you submit saves a full re-registration cycle.
New rule: variables must now be tagged by data type
Operator DLT platforms, including Airtel's, now require every variable in SMS templates created after 14 January 2026 to be tagged with its data type and purpose. A generic {#var#} placeholder is no longer sufficient; the platform only allows the type of data declared by the tag to be populated at send time.
Approved variable tags:
| Tag | Use for |
|---|---|
{#numeric#} | OTPs, amounts, numbers |
{#alphanumeric#} | Reference IDs, ticket numbers |
{#url#} | Website links |
{#urlott#} | OTT / app download links |
{#cbn#} | Callback numbers |
{#email#} | Email addresses |
Worked example: what this tool actually checks
Here's the same OTP template before and after running it through the checks above:
{#var#} placeholders (needs a data-type tag), a URL and a phone number (restricted for Promotional/Service Implicit templates unless pre-registered), and an emoji (forces Unicode encoding, raising SMS cost).Paste either version into the checker above (with the category set to Promotional or Service Implicit) to see these exact flags in action.
Variable placeholder format
Variables in a registered DLT template must use the {#...#} bracket syntax so the platform can tell dynamic content apart from fixed text, and as of the new rule above, must declare a data type inside it. Curly-brace styles like {name} or template-literal styles like ${var} are common mistakes carried over from coding syntax and will not be recognized.
Frequently Asked Questions
No. This tool checks common formatting issues, including variable placeholder syntax, character limits and disallowed patterns, that frequently cause DLT template rejections. Final approval depends on your telecom operator and the DLT platform's own review, including content-category matching.
DLT platforms in India require variable placeholders in registered templates to use a specific bracket syntax so the system can identify which parts of the message are dynamic content versus fixed text.
Under a directive rolled out on operator DLT platforms (including Airtel) for templates created after 14 January 2026, every variable must be tagged with its data type instead of using a generic placeholder. Approved tags include {#numeric#} for OTPs, amounts and numbers, {#alphanumeric#} for reference or ticket IDs, {#url#} for website links, {#urlott#} for OTT or app download links, {#cbn#} for callback numbers, and {#email#} for email addresses. Only data matching the declared tag can be populated at send time.
Promotional and service-implicit templates often restrict or disallow URLs, phone numbers and email addresses unless they are pre-registered with the template. Flag results are a prompt to double-check your template category rules, not an automatic rejection.
No. All checks run locally in your browser using JavaScript. Nothing you type is sent to or stored on our servers.
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