Translation

Generate natural-sounding captions in 30 languages from your source transcript.

Overview

Translation takes your transcribed captions and produces natural, spoken-register captions in your target languages. Unlike literal machine translation, Neolli’s pipeline is specifically tuned for video captions — it accounts for sentence boundaries, speaker context, timing constraints, and language-specific patterns.

Adding languages

1. From the video workspace, click Add Languages
2. Select target languages from the grid, or use a preset (Top 3, Top 5, Top 10)
3. Choose whether to generate captions, dubbing, or both
4. Click Start

Language presets select the most popular YouTube audience languages by reach. Top 3 covers ~60% of global YouTube viewers, Top 10 covers ~85%.

Supported languages

Neolli supports translation into 30 languages. See Supported Languages for the full matrix with transcription and dubbing availability.

How translation works

Neolli uses a 3-pass translation pipeline to balance accuracy, timing, and natural speech:

Caption translation

For caption translation, the pipeline runs three passes:

1. Translate — Sentence-aware translation that groups related segments and translates them as complete thoughts, maintaining speaker context and continuity
2. Condense — Shortens any segments that exceed their available display time, keeping a naturalness floor (minimum 3 words) to avoid choppy output
3. Polish — Fixes language-pair-specific issues like missing subjects (Korean), passive voice overuse (Japanese), or unnatural word order

Each pass is powered by Google Gemini, tuned for spoken-register output with language-specific guidance for all 30 languages.

Dubbing translation

For dubbing, translation uses content windows — complete thought units that may span multiple caption segments. This produces more natural speech for voice synthesis:

1. Window construction — Groups segments by speaker, gap threshold, and sentence boundaries
2. Translation — Translates entire windows as coherent units
3. Distribution — Maps translated text back to individual segment timestamps

The result is dubbed audio that flows naturally while staying synchronized with the video.

Metadata translation

When you translate a video, Neolli also translates the video’s title and description into each target language. This is especially useful when pushing to YouTube, where localized metadata helps international discoverability.

Editing translations

After translation completes, you can edit any segment in the caption editor. Changes are saved as a new version — you can switch between the AI-generated original and your edits at any time.

Credit cost

Translation is charged at 31 credits per 1,000 characters of source text, per language. A typical 10-minute video contains roughly 7,500 characters of speech. See Credit Costs for a detailed breakdown.