ModelRefs / Parameter Count — AI Glossary
Parameter Count — AI Glossary
The total number of trainable weights in a model; a rough proxy for capacity, commonly expressed in billions. A 7B model has 7 billion.
Overview
Parameters are the learned numerical weights in all linear layers. A 7B model has 7 billion. More parameters generally mean more knowledge capacity but higher inference cost and memory requirements. Mixture-of-experts models have high total parameter counts but activate only a subset per token, decoupling capacity from compute.
Reference details
| Topic | architecture |
|---|---|
| Also known as | model parameters, param count, weights |
| Last reviewed | 2026-06-24 |
Related terms
Example: Total, active, and what actually has to fit
Weights alone at fp16 cost 2 bytes per parameter: a 7B model is 7e9 × 2 = 14 GB before any KV cache. Quantised to 4 bits it is roughly 3.5 GB, which is why a laptop can run it. Mixture-of-experts breaks the link between size and cost in the other direction: Mixtral 8x7B holds about 46.7B parameters in total but routes each token through roughly 12.9B of them, so it needs the memory of a 47B model and the compute of a 13B one. One number for such a model tells you almost nothing.
Commonly confused with
Parameter count is a capacity proxy, not a quality measure. Training tokens, data quality and post-training often matter more, which is why smaller recent models beat larger older ones. For MoE, always ask whether a figure is total or active parameters — they answer different questions, memory and compute respectively.
When to use it
Reach for it when:
- Sizing hardware: memory footprint follows total parameters and precision directly
- Comparing models within one family and generation, where other variables are held still
- Estimating quantization headroom before committing to a deployment target
Reach for something else when:
- Predicting quality across families or generations — the correlation is weak
- Comparing dense and MoE models on a single number
- Cost modelling for hosted APIs, where you pay per token and never see the parameters
Continue your research
Use these connected ModelRefs sections to compare alternatives, inspect implementation paths, and review the evidence and governance boundaries relevant to Parameter Count — AI Glossary.
Frequently asked questions
What is Parameter Count?
The total number of trainable weights in a model; a rough proxy for capacity, commonly expressed in billions.
Is Parameter Count the same as model parameters?
Yes — model parameters, param count, weights are common aliases for Parameter Count.
What concepts are related to Parameter Count?
Closely related concepts include model size, model architecture, scaling law.