A model trained in sixteen-bit numbers can usually be served in eight or fewer with little measurable loss. Since token generation is bandwidth-bound, halving the bits roughly halves the work of reading weights — which makes quantisation one of the highest-return optimisations in serving.
In one sentence
Quantisation is the process of representing a model's weights, and sometimes its activations, in fewer bits than they were trained in, reducing memory footprint and bandwidth demand at some cost to numerical fidelity.
The reason it works is that neural network weights are heavily redundant and the arithmetic is tolerant of small errors. The reason it needs care is that the tolerance is uneven: most weights quantise cleanly, and a small number of outliers dominate the error if handled naively.
Practical schemes therefore quantise in groups with their own scaling factors, and often keep the few sensitive parts of the network at higher precision. Hardware support matters as much as the algorithm — a format the accelerator implements natively is fast, one that must be unpacked in software often is not.
How it works
Weights first, activations second
Weights are static and can be quantised offline with careful calibration, which is where most of the memory and bandwidth saving comes from. Activations change per request and are harder, because an unusual input can produce values outside the calibrated range. Many deployments quantise weights aggressively and activations conservatively.
Post-training versus quantisation-aware
Post-training quantisation converts an existing model using a small calibration set — cheap, fast, and adequate for most cases down to eight bits. Quantisation-aware training simulates the lower precision during fine-tuning so the model adapts to it, which costs a training run and is what makes very low precision viable.
Measuring what it cost
Aggregate benchmark scores hide selective damage: a quantised model can score the same overall while getting materially worse at one thing, often long-context reasoning or a less-represented language. Evaluating on the workload that matters, rather than on a leaderboard, is the difference between a safe optimisation and a silent regression.
What this depends on
Technology dependencies are solved by engineering; supply dependencies are solved by building something, which takes years.
Technology
Native low-precision hardware support
The saving is only realised if the accelerator executes the format directly rather than converting it back in software.
A format is only faster if there are tuned kernels that read it and matrix units that consume it. Without both, a smaller model is unpacked back to full precision and nothing is gained but memory.
Eight-bit and narrower formats are only portable between vendors because their exponent, mantissa and scaling rules are written down. Without that a quantised checkpoint would be specific to the chip it was produced for.
What depends on this
Other pages in this map that name Quantisation as something they cannot do without.
What each company supplies at this step, and — where a public figure exists — its share of this specific market — with what that share measures, the period it covers and who published it. Some rows also show the company’s own reported revenue for the segment covering this step, which is a different thing: it says how much this business matters to that company, not how much of the market it holds. Not a ranking and not a recommendation.
Defines the low-precision instructions the phone and laptop inference paths execute.
What would change the picture
How far usable precision falls before quality loss stops being acceptable for production workloads.
Whether models are increasingly trained in low precision from the start rather than converted afterwards.
Whether hardware and format support converge on a small number of standards or stay fragmented.
Questions people ask about this
Does quantisation make a model worse?
Slightly, and usually not noticeably at eight bits with a good scheme. Below that the loss becomes real and uneven — it tends to concentrate in specific capabilities rather than degrading everything a little, which is why it must be measured on the tasks that matter rather than on an average score.
Why does it speed things up so much?
Because generating a token is limited by reading the model's weights from memory, not by the arithmetic. Halving the bytes per weight roughly halves that read, and the arithmetic units were waiting anyway. The saving in memory footprint also allows larger batches, which compounds the gain.
Each page explains one technology in plain language, states what it depends on, and names companies by what they supply at that step. Company roles are described qualitatively and deliberately carry no market shares, revenue figures or rankings — those change faster than an explainer can, and a stale number is worse than none. Ticker links point at company pages on this site and are provided for reference only.
Nothing here is investment advice, a recommendation, or a forecast. A company named on a page about a technology is not thereby a good investment, and the chokepoints described are structural facts about supply chains rather than predictions about prices. Technology moves; where a page describes something as unresolved or in development, that was true when it was written.