Translate a PowerPoint presentation into Thai

What Thai changes on a slide

Thai is not dramatically longer than English in character count, but it uses space differently. Points worth knowing before you review:

• No spaces between words. A space separates sentences or clauses, not words, so lines can only be broken correctly with a dictionary. A break in the middle of a word, in a two-line title, is an obvious error to a Thai reader.
• Stacked marks. In น้ำ (water) or ที่, the vowel and tone mark sit above the consonant; in สุ the vowel sits below. A tightly set title line clips them.
• No full stop. Thai does not end sentences with a full stop, so bullets that end with one in your source will not in Thai. That is expected.
• No grammatical plural. Thai has a single plural category, "other": "3 new markets" becomes ตลาดใหม่ 3 แห่ง, with a classifier (แห่ง for places) after the number. Word order shifts, which matters if a figure is highlighted.
• Written register. Slides use formal written Thai, without the spoken politeness particles ครับ or ค่ะ.
• Dates. Official Thai documents often count years in the Buddhist Era: 2024 is 2567. Western digits remain common in business material.

Fonts and line height: the sensitive point

A .pptx theme stores one font for Latin script and a separate one for so-called complex scripts, Thai among them. If the theme font has no Thai glyphs, the computer opening the file picks a substitute, so the result can differ from one machine to the next, with different widths and heights.

• Choose a font that covers Thai, such as Leelawadee UI, Tahoma, Cordia New, Angsana New or TH Sarabun New, widely used in Thai public administration.
• At the same point size, some Thai fonts look noticeably smaller than their Latin counterparts: 14 pt may look thin on a projector. Judge legibility from the back of the room, not just on your monitor.
• Avoid line spacing fixed to an exact point value on titles: it cuts off tone marks above and vowels below. Single or multiple spacing leaves the room Thai needs.
• To share without any risk of substitution, use the PDF Manuce delivers, or embed fonts in the .pptx if your licence allows it.

What Manuce returns, and what it leaves untranslated

Manuce translates the text on every slide: titles, placeholders, text boxes, shapes, shapes inside groups and tables. You get your original .pptx back with the text replaced in place: theme, images, shape positions, animations and transitions stay as they were. The same content also comes as Word, PDF and plain text, handy for a Thai colleague who wants to proofread without PowerPoint.

What stays in the source language:

• Speaker notes, which are not translated at present.
• Chart and SmartArt text: legends, axis titles, data labels.
• Slide masters: a "Confidential" footer placed in the master stays as it is.
• Text inside images, screenshots included.

Two formatting limits matter more with Thai. A paragraph mixing several formats takes the formatting of its start, so a bold word mid-sentence loses its bold; Thai word order would not match yours anyway. And text box sizes are not recalculated: if Thai needs more height, it can overflow the bottom of a fixed box; any autofit set in PowerPoint still applies.

Thai carries a language supplement (×1.6 on the per-word rate). For a deck shown to Thai partners, the Professional tier is the one intended for text ready to send. Manuce does not provide certified (sworn) translation.

Preparing the file and checking the result

Before uploading:

• Convert SmartArt to ordinary shapes in PowerPoint if you want its text translated: shape text is.
• List the charts whose labels you will retype in Thai afterwards.
• Move text that needs translating out of the master (section subtitles, footer notices) and onto the slides.
• Turn on autofit for tight text boxes, or leave spare height.

After delivery:

• Open the .pptx on a machine with Thai fonts and compare it with the PDF.
• Ask a Thai reader to check two-line titles: that is where a bad line break shows.
• Check dates: does your audience expect 2567 or 2024?
• Check product names and acronyms that must stay unchanged, first in the free sample, then in the full translation.

In practice

1. Pick a theme font that includes Thai and loosen title line spacing.
2. Upload the .pptx: the quote appears at once, based on the exact word count.
3. Read the free Thai sample at your chosen tier, then start the translation.
4. Download the .pptx, the Word version, the PDF and the plain text.
5. Check line breaks, overflow, charts and dates before presenting.