Letters from Andrew Ng

Personal messages to the AI community

Cartoon of two coworkers coding; one struggles with evaluations, the other iterates quickly through model updates and test cases.
Letters

We Iterate on Models. We Can Iterate on Evals, Too: Building automated evals doesn’t need to be a huge investment. Start with a few quick-and-dirty examples and iterate!

I’ve noticed that many GenAI application projects put in automated evaluations (evals) of the system’s output probably later — and rely on humans to manually examine and judge outputs longer — than they should.
Black toddler sneakers with white soles on wooden floor, featuring Velcro strap and soft inner lining for comfort.
Letters

The Impact of U.S. Tariffs on AI: Broad tariffs will create challenges for AI and beyond, but I see a few silver linings. Here’s what’s in store.

I am so sorry that the U.S. is letting down our friends and allies.
Cartoon of a relaxed man saying “Relax! I’m lazy prompting!” while lounging under a beach umbrella near a stressed coworker at a desk.
Letters

The Benefits of Lazy Prompting: You don’t always need to provide context when prompting a large language model. A quick prompt can be enough.

Contrary to standard prompting advice that you should give LLMs the context they need to succeed, I find it’s sometimes faster to be lazy and dash off a quick, imprecise prompt and see what happens.
Cartoon of a man playing violin saying “I’m fine-tuning!” while a woman at her desk covers her ears, replying “Did you try prompting?”
Letters

When to Fine-Tune — and When Not To: Many teams that fine-tune their models would be better off prompting or using agentic workflows. Here's how to decide.

Fine-tuning small language models has been gaining traction over the past half year.
Top left: attendees watch a presentation. Top right: crowd at a developer booth. Bottom left: fortune cookie says ‘Build baby build!’ Bottom right: staff check in attendees.
Letters

Lessons From Our First AI Dev Conference: How our learners began building their way to AI in everything at AI Dev 25 Tags: Letters, DeepLearning.AI News, Learning & Education

Last Friday on Pi Day, we held AI Dev 25, a new conference for AI Developers.
Illustration of a programmer at a computer displaying PyTorch code, while a smiling colleague gives a thumbs-up in approval.
Letters

Learn the Language of Software: AI won’t kill programming. There has never been a better time to start coding.

Some people today are discouraging others from learning programming on the grounds AI will automate it.
Diagram of an RQ-Transformer speech system with Helium and Depth Transformers for audio processing.
Letters

Wait Your Turn! Conversation by Voice Versus Text: Text interactions require taking turns, but voices may interrupt or overlap. Here’s how AI is evolving for voice interactions.

Continuing our discussion on the Voice Stack, I’d like to explore an area that today’s voice-based systems mostly struggle with: Voice Activity Detection (VAD) and the turn-taking paradigm of communication.
Diagram comparing direct audio generation with a foundation model vs. a voice pipeline using STT, LLM, and TTS.
Letters

What I’ve Learned Building Voice Applications: Best practices for building apps based on AI’s evolving voice-in, voice-out stack

The Voice Stack is improving rapidly. Systems that interact with users via speaking and listening will drive many new applications.
Thermal aerial image showing a suspect surrendering with hands raised. A marker highlights their location.
Letters

How AI Saved a Police Officer’s Life: A police drone located an officer under attack before it was too late. Get ready for many more stories like this.

Last month, a drone from Skyfire AI was credited with saving a police officer’s life after a dramatic 2 a.m. traffic stop.
“Responsible AI” written on a wall, with “Safety” crossed out in blue paint.
Letters

The Difference Between “AI Safety” and “Responsible AI”: Talk about “AI safety” obscures an important point; AI isn't inherently unsafe. Instead, let’s talk about “responsible AI.”

At the Artificial Intelligence Action Summit in Paris this week, U.S. Vice President J.D. Vance said, “I’m not here to talk about AI safety.
Comic-style illustration of a confident woman and man standing beside bold ‘10X’ text on a bright background.
Letters

How AI can make you a 10x professional: Every profession can become more efficient and strategic by applying more intelligence.

A “10x engineer” — a widely accepted concept in tech — purportedly has 10 times the impact of the average engineer.
Three Takeaways from DeepSeek’s Big Week: Innvations by China’s AI powerhouse DeepSeek highlight major shifts in the international scene
Letters

Three Takeaways from DeepSeek’s Big Week: Innvations by China’s AI powerhouse DeepSeek highlight major shifts in the international scene

The buzz over DeepSeek this week crystallized, for many people, a few important trends that have been happening in plain sight.
Global temperature change map and graph comparing scenarios with and without SAI intervention.
Letters

How to Cool a Warming Planet: The only plausible path to keeping climate change in check is geoengineering.

Greetings from Davos, Switzerland! Many business and government leaders are gathered here again for the annual World Economic Forum to discuss tech, climate, geopolitics, and economic growth.
Two colleagues discuss their chatbot’s success; one suggests hiring an AI Product Manager.
Letters

AI Product Managers Will Be In-Demand: As the cost of building AI products falls, demand for people who know what to build will rise. Get ready for an explosion in AI Product Management!

Writing software, especially prototypes, is becoming cheaper. This will lead to increased demand for people who can decide what to build. AI Product Management has a bright future!
Illustration of tech tools like OpenAI, MongoDB, Heroku, and Python with Andrew Ng working on a laptop
Letters

My AI-Assisted Software Development Stack: The software development stack is evolving fast. Here are some things to consider as you choose components.

Using AI-assisted coding to build software prototypes is an important way to quickly explore many ideas and invent new things.

Subscribe to The Batch

Stay updated with weekly AI News and Insights delivered to your inbox