Saidwire

Real-time speech-to-text API

Wire-1: 50 ms p95 to final transcript.

Saidwire turns live English speech into text for voice agents, phone lines and live captions. Wire-1 ranked 1st of 29 on time to final segment in Coval's independent STT benchmark (30-day window to Nov 9, 2026).

50msp95 to final transcript, ranked 1st of 29 on time to final segment
2.9%word error rate on accented English, with 26 ms average to final transcript

Source: Coval independent STT benchmark, 30-day, Nov 2026 (accent figures: accented-speech dataset). Window ends Nov 9, 2026; 2,857 samples; US-hosted endpoint. Add your network round trip.

No card, no deadline. $0.25 per audio hour after the trial. Works with the OpenAI SDK and any /v1/listen-compatible client.

One turn, streamedFinal: 34 ms median (Coval)
Audio Speaker stops Interim words I'd liketo booka tablefor two Final transcript final, 34 ms
Interim results arrive while the person is speaking.
is_final with punctuation, plus speech_final for end of turn: "I'd like to book a table for two."

Schematic, not to scale. 34 ms median (p95 50 ms) to final transcript on Coval's STT benchmark (30-day window to Nov 9, 2026); add your network round trip.

Highlights

Measured independently, every day.

  • 1st of 29 on time to final segment: 35 ms average, 50 ms p95.
  • 1st of 29 on time to first token: 777 ms average.
  • Accented English: 3.1% word error rate, at 26 ms to final transcript.
  • Phone audio: 38 ms average to final transcript on phone-codec speech.
  • Accuracy overall: 3.8% word error rate.
  • $0.25 per audio hour: 120 free hours, no card, no deadline.

Source: Coval independent STT benchmark, 30-day, Nov 2026 (accent figures: accented-speech dataset). Window ends Nov 9, 2026; 2,857 samples; US-hosted endpoint. Add your network round trip. Method and how to reproduce

Demos

Hear it before you write a line of code.

Four ways to try Saidwire in under a minute: in your browser, on a phone call, or by listening.

LiveBrowser, microphone

Live speed test

Talk into your microphone. Each time you pause, a stopwatch shows how long the final transcript took.

Open the live speed test demo
LiveBrowser, microphone

Voice agent

Have a short spoken conversation with an example agent that hears you through the Saidwire API.

Open the voice agent demo
Phone line coming soonBrowser, microphone

Phone receptionist

Book a pretend appointment with an AI receptionist for a fictional dental office. Try it in your browser now.

Open the phone receptionist demo
LiveNo microphone needed

Audio samples

Play recorded clips and watch the transcript arrive exactly as the live API sent it.

Open the audio samples demo

All demos

Product

One API for live and recorded speech.

Streaming

Send audio over a WebSocket. Get interim words while the person speaks, then a punctuated final and an end-of-turn signal.

Streaming API

Files

Post a WAV, MP3, FLAC, Ogg or WebM file up to 60 minutes long and get the transcript back.

File transcription

OpenAI-compatible

Live now: POST /v1/audio/transcriptions works with the official OpenAI SDKs. Change the base URL and the key.

OpenAI-compatible endpoint

/v1/listen-compatible

Live now: already using a /v1/listen-compatible client? Change the base URL and the key. Your client code stays the same.

Switching guide

For developers

Two values to switch. A few lines to start.

Open a WebSocket, send audio, read JSON. Or keep the client you have and point it at Saidwire.

  • Interim results and finals. Live guesses while the person speaks, then text that will not change.
  • End of turn. Send Finalize when your voice detector says the user stopped, or let speech_final mark the pause.
  • Phone and web audio. μ-law, A-law and linear PCM from 8 to 48 kHz.
# Already using a /v1/listen-compatible client? Change two values.
- base URL   wss://<your current endpoint>/v1/listen
+ base URL   wss://api.saidwire.com/v1/listen
- API key    <your current key>
+ API key    sk_live_...

# Query parameters, Results messages, KeepAlive, Finalize and
# CloseStream keep the same names. Differences are listed in the docs.

Use cases

Built for speech that needs an answer now.

Voice agents

The final transcript lands 50 ms p95 after the end of speech (Coval, Nov 2026), so your agent can start its reply sooner. An end-of-turn signal comes with it.

Voice agents guide

Contact centers

Stream phone audio as it is: μ-law and A-law at 8 kHz, or linear PCM up to 48 kHz.

Phone bots guide

Meeting notes

Upload recordings in WAV, MP3, FLAC, Ogg or WebM, up to 60 minutes each, through our API or the OpenAI SDK.

Meeting notes guide

Live broadcasts

Transcribe press conferences, hearings and other live broadcasts as they happen, over the same streaming API.

Read the docs

Live captions

Interim words appear while the speaker talks; finals correct and punctuate them a moment later.

Live captions guide

Building something else?

Tell us what you are building and what you need from speech-to-text. We reply from the engineering team.

Tell us

Pricing

One price. A real free trial.

$0.25 per audio hour. Start with 120 free hours: no card, no deadline, up to 4 streams.

Free trial
$0to start
  • 120 free audio hours
  • No card needed
  • No deadline
  • Up to 4 streams at once
Start the free trial
Volume
Let's talk
  • Higher stream counts
  • Help moving an existing integration
  • A direct line to the engineers
Tell us what you need

Pricing details and cost calculator

Trust and security

Your audio is not kept.

Speech goes in, text comes out, and the audio is gone. Security or compliance questions go to support@saidwire.com.

Audio processed in memory

Audio is processed in memory and never stored. Transcripts are not stored or logged.

Encrypted connections

The API is served only over HTTPS and secure WebSockets (WSS).

Keys you control

Saidwire keeps only a hash of each key, so a lost key is replaced, never recovered.

A request ID on every request

Every stream and request returns a request ID, so support can find it without your audio.

Read the API privacy notice and API terms.

FAQ

Questions developers ask first

What do I get on the free trial?

120 free audio hours with no card and no deadline, and up to 4 streams at once. Sign up in the dashboard and get a key in a minute.

Is the API always on?

Yes. The API is always on; there is no warm-up window.

How do I switch from a /v1/listen-compatible integration?

Saidwire speaks the widely used /v1/listen streaming protocol. Change the base URL to wss://api.saidwire.com (or https:// for files) and use your Saidwire key. The compatibility notes list the few differences.

Can I use the OpenAI SDK?

Yes, for whole files. Set the base URL to https://api.saidwire.com/v1 and call audio.transcriptions.create. See OpenAI-compatible transcription.

Which languages and audio formats do you support?

English only. Streaming takes linear PCM from 8 to 48 kHz and μ-law or A-law phone audio. Files can be WAV, MP3, FLAC, Ogg or WebM, up to 60 minutes.

How fast is it?

50 ms p95 and 34 ms median to final transcript on Coval's independent STT benchmark (30-day window to Nov 9, 2026), ranked 1st of 29 on time to final segment; word error rate 3.8%. Add your network round trip. See Benchmark for the method.

How is usage counted?

Seconds of audio you send, from the first byte to the end of the stream, silence included.

Do you store my audio?

No. Audio is processed in memory and never stored.

Can I benchmark you and publish the results?

Yes. Tell us which datasets you used and we will link your results.

Start with 120 free hours.

No card, no deadline, up to 4 streams. Keep your client and change the URL.

Services

Two APIs, one model.

Live streaming API

For voice agents and live captions: stream audio over a WebSocket, get interim words while people speak and the final transcript when they stop.

Voice agents

File transcription API

For recordings: send a file or a URL, or use the OpenAI SDK.

File transcription

What's next

What we're working on.

  • Lower tail latency.
  • Better spelled names and email addresses.
  • Speaker labels on files.
  • More framework plugins.

Plans, not promises. Dated changes go on the changelog.

About

Saidwire

Saidwire LLC, Kansas City, Missouri, founded in 2026 by Hudson Leach. We build real-time English speech-to-text for voice agents. Contact: hudsonleach@saidwire.com.