AI Glossary Term

What does “Inference” mean?

Definition

The runtime phase where a trained model generates predictions or outputs.

How Inference works

Diagram for Inference, steps in order: Trained model, weights frozen; then New input arrives; then One forward pass or token-by-token generation; then Prediction or reply.Trained model, weights frozenNew input arrivesOne forward pass or token-by-tokengenerationPrediction or reply

Example

When you send a message to a chatbot, the provider runs inference: the already-trained model reads your message and generates a reply. No learning happens during that step.

Why it matters

Inference is the part users pay for and wait on. Its speed and cost affect product pricing, latency, and energy use.

Common questions

How is inference different from training?

Training adjusts the weights using data. Inference uses fixed weights to produce outputs.

Why can inference be expensive?

Large models need substantial memory and compute for each request, and popular services handle huge numbers of requests.

Can inference run on a phone?

Smaller or compressed models can, which is the aim of on-device AI.

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See also