Subtitles in your language or the one you're learning? What the research says

By SubPair team Published 2 November 2026

Short answer: subtitles in your own language help you follow the story; subtitles in the language you are learning help you learn to hear it. The best-known experiment on this found that same-language subtitles improved learners’ recognition of an unfamiliar accent, while native-language subtitles made it worse on new material. So use your own language while the plot would otherwise lose you, and switch to target-language subtitles as soon as you can follow most scenes with them.

Three words that get mixed up

Subtitles (interlingual): Audio in the language you are learning, text in your own language. Spanish audio, English text.
Captions (intralingual): Audio and text in the same language. Spanish audio, Spanish text. Researchers call these “captions” even when the streaming service calls them subtitles.
Reversed subtitles: Audio in your language, text in the one you are learning. English dub, Spanish text.
No text: The goal for most learners, and the hardest setting.

Most of the studies below compare captions with subtitles or with no text at all. Keep the distinction in mind: “watch with subtitles” advice is useless until you know which language they are in.

What the research found

1. Native-language subtitles can get in the way of hearing

In a study published in PLoS ONE, Holger Mitterer and James McQueen had Dutch university students with good English watch 25 minutes of either the Australian sitcom Kath & Kim or a shortened version of the Scottish film Trainspotting, with English subtitles, Dutch subtitles or none. Afterwards the students repeated short audio clips in that accent. English subtitles helped with both clips they had heard and new ones. Dutch subtitles helped with clips they had already heard (they knew what was coming) but made them worse than no subtitles on new clips. The authors’ explanation: native-language text creates “lexical interference”, so your brain maps the sound to the meaning on screen instead of to the foreign words (Mitterer & McQueen, 2009).

The study is about adapting to an accent, not about vocabulary or grammar, and the participants were already good at English. But it matches what many learners notice: with subtitles in your own language you read the story and stop listening.

2. Captions help listening and vocabulary

A meta-analysis that pooled the experimental studies available at the time found that captioned video clearly improved both listening comprehension and vocabulary learning compared with watching without captions (Montero Perez, Van Den Noortgate & Desmet, 2013). A later review and meta-analysis of vocabulary studies again found a positive effect of watching captioned or subtitled video (Reynolds, Cui, Kao & Thomas, 2022).

3. One episode teaches a few words, many episodes teach many

When learners watched a single full-length TV programme without being asked to study anything, they did pick up new words, but not many. The words they learned were the ones that came up repeatedly, the ones similar to words in their own language, and learners who already knew more vocabulary learned more (Peters & Webb, 2018). Watching is a slow, steady source of words, not a fast one, which is why the number of episodes matters more than the perfect setting for any one of them.

4. You need fewer words than you think, but not few

An analysis of the language in 88 television programmes found that the 3,000 most frequent word families, plus proper nouns and marginal words like “um”, covered about 95% of the words spoken (Webb & Rodgers, 2009). At 95%, one word in twenty is still unknown, roughly one per subtitle line or two. That is the zone where captions help most: you understand enough to follow, and the text shows you the words your ear missed.

Why your own language still has a place

None of this means native-language subtitles are useless. If you understand a third of the dialogue, captions in the target language just show you a wall of unknown text at speed, and you will stop watching. Enjoyment is not a side issue: the studies above all point to quantity of exposure, and you only get quantity from shows you actually want to finish.

Your own language is also the fastest way to check a line you couldn’t parse. The problem is not looking at it; it is reading it by default, every line, for months.

Showing both lines at once (dual or bilingual subtitles) sits in between. Research on bilingual subtitles is newer and smaller than the studies above, so treat it as a practical bridge rather than a proven method: let your eyes start on the target-language line and drop to your own language only when you get stuck.

A rule for switching

Run this five-minute test at the start of an episode:

Watch five minutes with captions in the language you are learning.
Ask yourself: do I know what happened, and could I explain it to someone?
If yes, keep target-language captions for the episode.
If you followed the gist but lost whole exchanges, keep captions and allow yourself your own language on the lines you replay.
If you lost the plot, switch to your own language for this show, or pick an easier one: a sitcom or a series you have already seen dubbed.

Repeat the test every few weeks. Most learners find they move up a stage on familiar shows long before they can on new ones, which is a good reason to stay with one series for a while: a show reuses its characters’ vocabulary episode after episode.

Get more from each line

Replay instead of reading ahead. When a line goes past, go back and listen again before you look at the translation. Many players skip back ten seconds; some tools replay exactly one subtitle line.
Notice what the text leaves out. Subtitles are condensed for reading speed, so fillers and contractions often vanish. Listen for them.
Keep the line with the word. If you save a word, save the sentence it came from. Our guide to learning vocabulary from TV shows explains how to review it so it sticks.

For a full setup on Netflix, including which tracks to pick, see how to learn English with Netflix.

Sources

Mitterer, H. & McQueen, J. M. (2009). Foreign subtitles help but native-language subtitles harm foreign speech perception. PLoS ONE, 4(11), e7785. doi.org/10.1371/journal.pone.0007785
Montero Perez, M., Van Den Noortgate, W. & Desmet, P. (2013). Captioned video for L2 listening and vocabulary learning: a meta-analysis. System, 41(3), 720–739. doi.org/10.1016/j.system.2013.07.013
Reynolds, B. L., Cui, Y., Kao, C.-W. & Thomas, N. (2022). Vocabulary acquisition through viewing captioned and subtitled video: a scoping review and meta-analysis. Systems, 10(5), 133. mdpi.com/2079-8954/10/5/133
Peters, E. & Webb, S. (2018). Incidental vocabulary acquisition through viewing L2 television and factors that affect learning. Studies in Second Language Acquisition, 40(3), 551–577. doi.org/10.1017/S0272263117000407
Webb, S. & Rodgers, M. P. H. (2009). The vocabulary demands of television programs. Language Learning, 59(2), 335–366. doi.org/10.1111/j.1467-9922.2009.00509.x