For FIFA World Cup 2026, one caption engine fed CEA-608 captions to Fan Zone big screens and a live caption page in the official app, so fans could follow the commentary from any seat.
Read case study SyncWords Live AI Captioning
Live captions for streams, events and video files
Live AI captioning for broadcast, streaming and events. A satellite channel, a commencement, a city council meeting, a forty-year-old archive tape: one caption pipeline puts the words inside the stream, on a phone, on a wall or into a file.
- No hardware encoder
- No per-channel licence
- AI or professional CART
The cross comes in, headed home for 2–1 
Markets rallied across Asia today 
Live captions are on in six languages Trusted when the words have to arrive live
Case studies
Captions in production
From World Cup fan zones to state legislatures and church services. What we built, and how it turned out.
Weigel added live same-language captions across its regional news stations, covering its caption obligations without standing up a human captioning team.
Read case study
For the Texas Legislative Council, cloud captioning replaced the on-prem caption encoder: live streams go to SyncWords, captions come back embedded, and the contract keeps renewing.
Read case study
As producer of CHI 2026, Executive Events extended live captioning across every stage and session: attendees scan a QR code and read in their browser.
Read case study
For Mantis Broadcast at London Tech Week, live caption pages reached a high-profile audience with the reliability a flagship event demands.
Read case study
For HLTH, attendees just scan a QR code for live captions on their phones. Full in-room accessibility with nothing to install or set up.
Read case study
For the CDC, live captioning across three concurrent sessions over four days kept a major public event fully accessible without extra staffing.
Read case study
For Victory Church in the Bronx, live AI captions run by the church's own staff make every live-streamed service accessible to deaf and hard-of-hearing members.
Read case studyLooking for the commercial answer?
Start with the room you run
SyncWords Live
Put captions inside the stream
Choose the seam in your chain. We join it without re-encoding the video or asking you to replace the vendors around it.
SRT before the transcoder
Embedded EIA-608 for North American chains, with Teletext, DVB-SUB and DVB-TTML for broader scripts and markets.
HLS at the origin
Write WebVTT into the stream you already publish. The CDN and players stay untouched.
RTMP for social destinations
Point any RTMP(S) encoder at SyncWords and send a captioned output onward.
The encoder you already own
Drive existing caption hardware over IP while you migrate at your own pace.
Caption timing
Half a second to the video. Under two to the captions.
On an SRT workflow with no added buffer, SyncWords can add as little as half a second to the video path while caption delay stays typically under two seconds.
- ½ second
- as little as we add to the SRT video path
- <2 seconds
- typical caption delay in the same workflow
Live monitoring
The numbers your operator watches
Wherever the room is, the service looks the same from the booth: stream health, caption delay and every output language on one screen while you're on air.
- Stream health and caption delay at a glance
- Every output language and where it's going
- Catch trouble before the audience does
live.syncwords.com/services/48105
Live Commencement — Main stage
48105 SRT → SRT Acme Media, live desk
Stream monitoring Beta
In bitrate
24.8Mbps
Incoming media rate
In RTT
12ms
Round-trip to source
Out bitrate
24.6Mbps
Outgoing delivery rate
Out RTT
9ms
Downstream round-trip
Transcript
83,859
Characters transcribed
Translation
412,304
Characters translated
Dubbing
46 min
Dubbed minutes
Session
3h 03m
Processed audio time
Monitoring dashboard →
EN
ES FR DE JA AR
Events
Put the words on every phone and every wall
Start a session and get a URL plus a QR code in under 60 seconds. No video is required. A microphone and a browser are enough.
See the Events platformAttendee phones
One scan opens a branded caption page with no app to install.
In-room screens
Route the live caption page through OBS to the confidence monitor or house display.
Virtual rooms
Deliver into Zoom, Microsoft Teams and Adobe Connect, or embed the widget in the event platform.
After the live session
The transcript is yours
Export the original words or any translated language as plain text, SRT, WebVTT or DFXP. Take the whole session or the exact time window you need.
Explore the Live APITimecodes that match your recording
Start from the selected window, align to the program feed or reset the first caption to 00:00:00.
Ready for the next system
Request an export through Live API v2, follow its status and collect the finished file automatically.
Every session language
Export the original language or any translation already running on the service.
Four useful formats
Download plain text, SRT, WebVTT or DFXP for editing, publishing or archiving.
VOD Express
We also do VOD
Send us video or audio files and get captions, subtitles, dubbed audio or a multilingual video master back automatically.
Explore VOD ExpressBuilt for backlog-sized volume
Daily clips, user uploads and large libraries move through in parallel.
The package you declare
Return standalone captions, muxed subtitle tracks, dubbed audio and multilingual video masters in the combination your workflow needs.
Professional CART
Put a human where the moment calls for one
Book a professional captioner through the same platform in English, Spanish, Portuguese or French. Bring your own trusted captioner if you prefer.
Human on the keynote
Reserve professional CART for the highest-profile moments on the agenda.
AI on every breakout
Carry the rest of the agenda without multiplying vendor coordination.
Choose session by session
Assign professional CART or AI to each room without moving the event between vendors.
Live captioning questions worth asking
What is live captioning?
Live captioning turns speech into on-screen text while the program is still on air. SyncWords writes the captions with AI, or with a professional CART captioner when you book one, and delivers them inside the stream as EIA-608, Teletext, DVB-SUB, DVB-TTML or WebVTT, on a caption page attendees open with a QR code, or both at once.
Do I need a caption encoder for live captioning?
No. SyncWords joins your stream in the cloud over SRT, HLS or RTMP and writes the captions without re-encoding the video. If you already own caption encoders, SyncWords can drive them over IP while you migrate at your own pace.
How fast do live captions appear?
In an SRT workflow the video path itself adds a half-second latency, and caption delay stays typically under two seconds. On the live events caption page, captions are typically 1-3 seconds end-to-end from spoken word to caption display. How latency, processing time and delay differ.
Will this make our organization compliant?
Compliance rests with your organization. SyncWords gives you the output side of the job: captions built to the FCC Title V criteria for accuracy, synchrony, completeness and placement, in the formats regulators and distributors ask for.
Do you output CEA-708?
SyncWords outputs EIA-608. Downstream systems that expect 708 receive the 608 carried inside it.
Which languages can you caption live?
AI live captioning covers 90 source languages, with automatic source-language detection. Professional CART is available in English, Spanish, Portuguese and French. Embedded EIA-608 carries the seven languages the standard supports, including English, Spanish, French, Portuguese and Italian, while WebVTT, DVB-SUB and DVB-TTML carry non-Latin scripts. To show the words in another language, add translated subtitles.
How accurate are AI live captions?
Accuracy starts at ingestion. With clean program audio and a custom ASR dictionary for your names and terminology, live captioning delivers best-in-class word accuracy. Because every translation is built from that transcript, dictionary quality carries into every subtitle and dub language.
What happens with names and terminology?
Custom ASR dictionaries help the captioning engine recognize names, acronyms and specialist terms. Translation glossaries control the preferred wording in each target language.
Can I export the transcript after a live session?
Yes. Export the source language or any translated language as plain text, SRT, WebVTT or DFXP. You can choose an exact time window and align its timecodes to the recording.
How is live captioning priced?
Pricing follows the live hours and caption outputs you run, not the number of channels you keep configured. There is no per-channel licence, and the effective hourly rate falls as committed volume rises.
Bring the stream, the room or the difficult file
We will put captions where you need them and show you the path in a live session.