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Writing a script that TTS reads well

The same voice can sound natural or stilted depending on the script. TTS reads exactly what is written, so phrasing that looks fine on the page often snags on the ear. Following the points below alone makes a visible difference to the result.

The examples here are Korean, because that is what most people put through this site — but the principles (short sentences, punctuation for pauses, numbers written as spoken) apply to any language.

1. One idea per sentence

When a sentence runs long, TTS finds nowhere to breathe and reads it flat. Past about 40 characters, split it in two.

Before이번 행사는 다음 주 토요일에 열리며 참가 신청은 이번 주 금요일까지 홈페이지에서 할 수 있고 선착순 백 명에게는 기념품을 드립니다.
After이번 행사는 다음 주 토요일에 열립니다. 참가 신청은 이번 주 금요일까지 홈페이지에서 할 수 있습니다. 선착순 백 명에게는 기념품을 드립니다.

2. Commas are breath — spaces are not

TTS pauses briefly at a comma and a little longer at a full stop. Put a comma before a word you want to stress, or where the listener needs a moment to take something in. Too many commas, though, and it sounds chopped up.

Pressing the space bar repeatedly or adding blank lines does nothing. Runs of spaces collapse into one during conversion, and line breaks are simply read through. To create a pause, use punctuation, not whitespace.

What you typePauseUse it for
, commaShortSeparating groups of words
. full stopMediumEnd of a sentence
… or ...Slightly longerLetting something linger
? !Medium, plus intonationQuestions and emphasis

2-1. When you need an exact number of seconds

Pauses from punctuation cannot be given a length. If you need exactly two seconds here, use Script mode: set Gap between lines under Script settings and that much silence goes between every line (0–2 seconds).

You do not need several characters for this. Write several lines under the same name and one voice reads them with a pause after each.

One voice, with even gapsReader: 다음 문장을 따라 읽어 보세요. Reader: 오늘은 날씨가 좋습니다. Reader: 내일은 비가 올 것 같습니다.

It suits anything where the spacing has to be even — language-listening material, phone greetings, meditation and breathing guides.

3. Check how numbers come out

Depending on context, a digit can be read in more than one way. Most of the time it is fine, but for a number that matters, preview it — and if it sounds wrong, write it out in words.

WrittenWrite it like this instead
1,500원천오백 원
2시 30분두 시 삼십 분
3~5일삼 일에서 오 일
제1조제일 조

4. Write dates and times as you would say them

Forms like "2026.09.21", "2026. 10. 13." and "9/21" can have the dots and slashes read aloud, or come out wrong. Write them the spoken way instead. Note that in Korean the month names for October and June are 시월 and 유월, not 십월 or 육월 — listen, and if it sounds off, spell it out.

5. Phone numbers one digit at a time

Left as "1588-1234", it may be read as one large number. For an announcement, write it digit by digit — "일오팔팔, 일이삼사" — with a comma between groups, which also makes it easier to write down.

6. Register abbreviations once

For abbreviations that recur — AI, KPI, NH — register them once under Pronunciation fixes on the main screen ("AI → 에이아이") instead of editing every script. The audio uses the corrected pronunciation while the subtitles keep the original spelling.

Left as plain letters, they are often run together into a single mangled word, especially abbreviations containing a slash.

WrittenRegister it as
UI/UX유아이 유엑스
PDF피디에프
AI에이아이
Q&A큐 앤 에이
USB-C유에스비 씨

7. Drop brackets, or turn them into sentences

For a listener, a parenthesis breaks the flow. If the information is necessary, make it a sentence.

Before신청서(별지 제2호 서식)를 작성해 주세요.
After신청서를 작성해 주세요. 서식은 별지 제이 호입니다.

8. Turn symbols and units into words

Symbols such as ~, /, &, % and → are either skipped or read awkwardly. Make "A/B" into "A or B", "%" into "per cent", "&" into "and". Emoji and decorative characters are best removed entirely.

Numbers with units go wrong especially often. Spell the unit out and put the digits in spoken order.

WrittenWrite it like this instead
10km/h시속 십 킬로미터
5,000mAh오천 밀리암페어시
180g백팔십 그램
24℃이십사 도
1/2이분의 일
A4 용지에이포 용지

9. Put question marks and exclamation marks to work

A question mark lifts the end of the sentence; an exclamation mark adds a little force. Narration that opens with a question ("Has this ever happened to you?") is good at catching attention. Scatter exclamation marks everywhere, though, and it sounds overblown.

10. Always listen before you commit

When the script is done, preview the opening before rendering the whole thing. There is always something only the ear catches. Check proper nouns, numbers and any technical term appearing for the first time; where there is a problem, add a pronunciation fix or change the script.

On one line

Short sentences · pauses from punctuation, not spaces · exact seconds via Gap between lines in Script mode · numbers, dates and phone numbers as spoken · abbreviations in Pronunciation fixes · brackets and symbols written out · preview before you create

Before and after

Applying all of the above to real sentences looks like this. Put both versions in and listen — the difference is obvious.

Notice · before9/30(월) 10:00~12:00 시스템 점검 예정(※접속 불가)
Notice · after구월 삼십일 월요일, 오전 열 시부터 열두 시까지 시스템 점검이 있습니다. 점검 시간에는 접속할 수 없습니다.
Product description · before본 제품은 USB-C 타입, 5000mAh 용량, 무게 180g으로 휴대성이 뛰어나며 고속충전(PD 20W)을 지원합니다.
Product description · after이 보조배터리는 유에스비 씨 타입을 씁니다. 용량은 오천 밀리암페어시, 무게는 백팔십 그램으로 가볍습니다. 이십 와트 고속 충전도 됩니다.
Contact notice · before문의사항은 고객센터(1588-0000) 또는 홈페이지 Q&A 게시판 이용 바랍니다.
Contact notice · after궁금한 점은 고객센터로 전화 주세요. 번호는 일오팔팔, 공공공공입니다. 홈페이지 질문 게시판도 이용하실 수 있습니다.

Script polished? Put it in and listen.

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Related guides

Making YouTube narration: from script to subtitles (SRT)How to make narration for YouTube videos and Shorts with TTS. Make your own phone greetings: example wording and settingsExample wording for main-number greetings, after hours, lunch break, holidays and hold messages, the TTS settings to use, and what to watch for when loading them into phone hardware. Dialogue audio with Script mode: audio drama, training material, role-playHow to turn a back-and-forth conversation into a single TTS file.