Slam 1 API

aai/slam-1
Slam-1 represents a major advancement in speech AI by seamlessly combining language understanding with speech transcription, tailored for enterprise needs.
Output
$0.0000975 / sec
Released
Dec 30, 2025

Overview

Slam-1 is AssemblyAI's groundbreaking Speech Language Model (SLM) that unifies large language model architecture with advanced automatic speech recognition (ASR) encoders to deliver superior speech-to-text transcription accuracy. Designed specifically for speech tasks, Slam-1 understands context and semantics at a deep level, enabling promptable and customizable transcription that adapts to specialized industry terminology and complex spoken content. This makes Slam-1 ideal for use cases in healthcare, legal, sales, and technical domains requiring precise and context-aware transcription.

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Technical Specifications

Performance Benchmarks

  • Reduces missed entity rates by up to 66%, especially for names, medical, and technical terms.
  • Decreases formatting errors by approximately 20%.
  • Preferred by over 72% of end users in blind tests versus competing models.
  • Achieves more reliable transcript quality in noisy and specialized contexts versus previous models.
  • Delivers robustness against hallucinations through a multi-modal architecture that simultaneously processes audio and language.

Architecture Breakdown

Slam-1’s architecture distinctively merges a speech encoder with an adapter layer tuned to link acoustic features with a fixed large language model, enabling powerful semantic understanding. This multi-modal design surpasses traditional audio-to-text models by interpreting spoken content holistically, supporting accurate transcription and contextual reasoning. The approach leverages prompt engineering to customize transcription accuracy dynamically for industry-specific vocabularies and speech patterns.

API Pricing

  • $0.00325 per min

Core Features & Capabilities

  • Speech and Language Integration: Combines speech encoder and LLM for promptable and customizable transcription workflows.
  • Fine-Tuning & Customization: Enables domain-specific adaptation through simple prompts without retraining.
  • High Accuracy: Superior recognition of rare and domain-specific terms, improving downstream analytics and reducing manual review.
  • Multi-Channel & Speaker Diarization: Supports complex audio streams with speaker separation and timestamps out of the box.
  • Enterprise Ready: Designed to reduce post-processing effort and improve transcript quality in high-stakes industries like healthcare and legal.

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Code Sample

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Comparison with Other Models

VS AssemblyAI Universal: Slam-1 offers promptable, highly customizable transcription with superior entity recognition for specialized domains, while AssemblyAI Universal provides broader language support and lower latency for general transcription needs.

VS GPT-4.1 (audio transcription use): Slam-1 is specifically optimized for speech-to-text with multi-channel and speaker diarization features, unlike GPT-4.1, which focuses on general NLP tasks without native audio processing capabilities.

Use cases

  • Medical scribing with enhanced capture of prescription names, diagnoses, and medical terminology.
  • Legal transcription with improved accuracy for case citations, legal phrases, and procedural terms.
  • Sales and contact center call analysis benefiting from better recognition of product names and company details.
  • AI-powered meeting notes and content analytics with reduced error rates and formatting issues.

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How to use Slam 1 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to aai/slam-1.
import requests, time

headers = {"Authorization": "Bearer " + AIMLAPI_KEY}
job = requests.post(
    "https://api.aimlapi.com/v1/stt/create",
    headers=headers,
    json={
      "model": "aai/slam-1",
      "url": "https://example.com/audio.mp3"
    },
).json()
gid = job["generation_id"]

while True:
    res = requests.get(f"https://api.aimlapi.com/v1/stt/{gid}", headers=headers).json()
    if res.get("status") in ("completed", "error", "failed"):
        break
    time.sleep(3)
print(res)
const headers = {
  Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
  "Content-Type": "application/json",
};
const job = await (await fetch("https://api.aimlapi.com/v1/stt/create", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "model": "aai/slam-1",
    "url": "https://example.com/audio.mp3"
  }),
})).json();

let res;
do {
  await new Promise((r) => setTimeout(r, 3000));
  res = await (await fetch(`https://api.aimlapi.com/v1/stt/${job.generation_id}`, { headers })).json();
} while (!["completed", "error", "failed"].includes(res.status));
console.log(res);
# submit the job — the response contains "generation_id"
curl -X POST https://api.aimlapi.com/v1/stt/create \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"aai/slam-1","url":"https://example.com/audio.mp3"}'

# then poll for the result until it is ready
curl "https://api.aimlapi.com/v1/stt/{generation_id}" -H "Authorization: Bearer $AIMLAPI_KEY"

OpenAI-compatible — swap the base URL and it works with your existing SDK.

Slam 1 API Pricing

TypePrice
Output
$0.0000975 / sec

Slam 1 vs other models

ModelInputOutputContextBest for
Slam 1
This page
$0.0000975 / sec
Transcription
$130 / 1M characters
$130 / 1M
Speech synthesis
$130 / 1M characters
$0.13 / 1M tokens
Speech synthesis
$78 / 1M characters
$0.078 / 1M tokens
Speech synthesis
$13 / 1M characters
$0.013 / 1M tokens
Speech synthesis

Frequently asked questions

Slam 1 takes audio as input and returns text.

Slam 1 is priced at output $0.0000975 / sec.

Slam 1 was built by Assembly AI.

Send a request to v1/stt/create with aai/slam-1 as the model id.

Yes. Slam 1 is served through AI/ML API, so the same key and endpoint format used for other models applies.

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