Manipulate how text is spoken using Speech Synthesis Markup Language (SSML) tags and text normalization. This helps you configure prompts that align with brand tone and clarity, while accommodating multilingual and regulated enterprise scenarios.
Required Editions
| View supported editions. |
This article applies to:
Salesforce Voice (Native Telephony)
Supported SSML tags are <break> and <phoneme>.
Here is syntax and examples for these tags:
<break>- inserts a pause between words or sentences. Specify the length of the pause using the
time attribute. For example,
<break time="0.5s"/>. The time duration is in seconds and you can enter a maximum duration of 3 seconds. For example, Thank you for calling.<break time="1s"/>Please stay on the line. <phoneme>- customizes pronunciation using a phonetic alphabet like the Carnegie Mellon University (CMU) Pronouncing Dictionary and the International Phonetic Alphabet (IPA). We recommend using the CMU alphabet for consistent and predictable results with more reliable performance.
| Feature / SSML Tag | English | Non-English Language | Notes |
|---|---|---|---|
| SSML Tag: <break> | Yes | Yes | Accepts fraction. |
| SSML Tag: <phoneme> | Yes | No | Supports CMU/IPA |
| Text Normalization | Yes | Yes | Dates, numbers currency, acronyms |
Phoneme tags only work for individual words. For example, if you have a first and last name
that you want to be pronounced a certain way, you must create a phoneme tag for each word. An
example in the CMU Alphabet is <phoneme alphabet="cmu-arpabet" ph="M AE1 D IH0 S
AH0 N"> Madison </phoneme>
The prompt also supports text normalization that converts raw input text into a more natural, spoken form before it's rendered by the TTS engine. Here are some examples of how text to speech is rendered with normalization.
| Input | With Text Normalization |
|---|---|
| €99 | Ninety nine euros |
| 12/08/2025 | Twelfth of august two thousand and twenty five |
| www.example.com/link/to/resource | Double double double dot example dot com slash link slash to slash resource |
| 3.14 | Three point one four |
| 5 kg | Five Kilo Gram |
| 15th Jan | Fifteenth of January |
| 12:00 PM | Twelve PM |