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LLMs or JEPA?

DimensionLarge language modelsJEPA (Joint-Embedding Predictive Architecture)
In one linePredict the next token of text, one at a time, and keep goingPredict the representation of a hidden part of the input, never its pixels or tokens
Training signalSelf-supervised on raw text: the next token is the label, so trillions of tokens need no annotationSelf-supervised on images or video: mask regions and predict their embeddings, with no labels, text or negatives
What it outputsText (or code, or JSON), sampled token by token from a probability over the vocabularyEmbeddings. Text or actions come from a probe, a decoder or a planner built on top
Handling the unpredictableSpreads probability over a finite vocabulary, which works for discrete textEncoders drop details that can’t be predicted; a latent variable can stand for the remaining choices
Main dataText and code from the web and booksImages and video: V-JEPA 2 used over 1 million hours of video and 1 million images
Typical sizeBillions to hundreds of billions of weights: Qwen3-8B has 8.2 billion, DeepSeek-R1 671 billionAround a billion: I-JEPA’s ViT-H is 632 million parameters, V-JEPA 2 is 1.2 billion
PlanningIn text: the model writes out steps, or an agent loop calls tools and feeds results backIn the world model: V-JEPA 2-AC searches action sequences whose predicted state lands closest to a goal image
Maturity in October 2026Products: hosted APIs from many providers and open-weight models you can run locallyResearch: papers, code and checkpoints from Meta FAIR; AMI Labs founded to build on it, with no product planned for years
Licences of the best-known modelsProvider terms for APIs; Apache 2.0 (Qwen3) or the Llama Community License for open weightsMIT for V-JEPA 2; CC BY-NC 4.0, non-commercial, for I-JEPA and V-JEPA
Weak spotsFluent but sometimes wrong; knows only what is in its training data or context; LeCun argues its common sense is shallow without experience of the physical worldCan’t say or draw anything on its own; robot success of 65% to 80% on pick-and-place in lab tests; most published results are on images and video

Rule of thumb

They answer different questions. Use an LLM when the input or output is text and you need a working product today. Look at JEPA when the input is video or sensor data and you want a frozen encoder or a world model to plan with, and accept that it is research code. The two are starting to meet: LLM-JEPA adds a JEPA objective to LLM training, and VL-JEPA answers questions by predicting text embeddings.

Sources