Slam 1 API

AssemblyAI's most customizable model for transcription (English only).

Modalities
AudioText
Model type
Speech to text
Released
Dec 30, 2025

Slam 1 overview

Slam 1 by Assembly AI

It offers substantial gains in accuracy and adaptability, directly improving transcription workflows in complex real-world environments.

Slam 1 specs

Model ID
aai/slam-1
Developer
Assembly AI
Input
Audio
Output
Text
Endpoint
POST https://api.aimlapi.com/v1/stt/create

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.

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.

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.

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.

How to use the Slam 1 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/stt/create' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "aai/slam-1"
}'

The request returns a generation id. Poll GET https://api.aimlapi.com/v1/stt/create?generation_id=<id> until the status is completed.

Related articles

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Slam 1 FAQ

What inputs and outputs does Slam 1 support?

Slam 1 takes audio as input and returns text.

How much does Slam 1 cost?

Slam 1 is priced at output $0.0000975 / sec.

Who created Slam 1?

Slam 1 was built by Assembly AI.

How do I call Slam 1 on AI/ML API?

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

Is Slam 1 available through a single API key?

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

What is the Slam 1 model ID?

Use aai/slam-1 as the model parameter. Requests go to https://api.aimlapi.com/v1/stt/create with your AI/ML API key.

Start building with Slam 1

Slam 1 API

aai/slam-1

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/stt/create' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "aai/slam-1"
}'