AlexaTM 20B

Closed weights Amazon 19.8B parameters August 2022

No estimate

No hardware requirements for this model

The weights for this model have not been published, so it cannot be downloaded or run on your own hardware at any size. It is reachable only through its provider, and no graphics card changes that.

On record

Full specification

Everything on record for this model. Most of it describes how it was trained rather than how it runs — useful context for judging how much work went into it, and how it compares with models built at a different scale.

Origin

Who built this model, where, and when it was published.

Organisation
Amazon
Organisation type
Industry
Country
United States of America
Published
2 August 2022
Authors
Saleh Soltan, Shankar Ananthakrishnan, Jack FitzGerald, Rahul Gupta, Wael Hamza, Haidar Khan, Charith Peris, Stephen Rawls, Andy Rosenbaum, Anna Rumshisky, Chandana Satya Prakash, Mukund Sridhar, Fabian Triefenbach, Apurv Verma, Gokhan Tur, Prem Natarajan

What it does

The problem areas the model was built for. A model can carry several of each.

Domain
Language
Task
Language modeling, Translation, Question answering
Numerical format
BF16

Size

How large the model is and how much data it was trained on. Parameters are the figure that decides whether it fits on a given graphics card.

Parameters
19.8B

See Table 1 on p.3 of the paper

Training data
1,319,000,000,000 tokens

See Table 2 on p.3 of the paper. 119B Wikipedia tokens + 1.2T mC4 tokens = 1319000000000 tokens

Batch size
2,000,000

"We trained AlexaTM 20B for 120 days on 128 A100 GPUs for the total of 500k updates with the accumulated batch size of 2 million tokens"

Training compute

The arithmetic performed to train the model, measured in floating-point operations. It is a measure of what the training run cost, not of how fast the finished model answers you.

Training compute
2 × 10²³ FLOP

Training throughput is reported as 154 TFLOP/s - see p.5 of the paper. "We relied on an internal and optimized version of DeepSpeed that we have since open-sourced (Chiu & Zheng, 2022) to obtain training throughput of up to 154 TFLOPS/GPU on 16 AWS p4d.24xlarge compute instances." Accelerator compute days are reported as 15,360 days - see Table 17 on p.18 of the paper.

How it was established
Hardware

The training run

What it physically took to train: which chips, how many, for how long, and what that drew from the wall.

Training hardware
NVIDIA A100
Chips used
128
Chip-hours
368,640
Wall-clock time
2,880 hours (120 days)

See p.5 of the paper: "We trained AlexaTM 20B for 120 days on 128 A100 GPUs..."

Hardware utilisation
HFU 49.4%

Training throughput reported at 154 TFLOPs/GPU, vs 312 TFLOPs/GPU for the A100s they use HFU = 154e12 / 312e12 = 0.4935

Power draw
102.6 kW
Compute cost
$267,943
Cloud vendor
Amazon Web Services

Availability

Whether you can obtain the model and run it on your own hardware, which is what decides if any of the graphics-card figures on this page apply.

Weights
Closed — provider access only
Model access
API access
Training code
Unreleased

https://aws.amazon.com/about-aws/whats-new/2022/11/alexatm-20b-model-available-sagemaker-jumpstart/?nc1=h_ls

How it is classified

Labels the source dataset applies when tracking notable models, and how confident it is in the entry.

Likely above 10²³ FLOP
Yes
Why it is tracked
SOTA improvement

The Abstract reports SOTA improvement on multiple benchmarks. "provides SOTA performance on multilingual tasks such as XNLI, XCOPA, Paws-X, and XWinograd"

Record confidence
Confident
Citations
90

Sources

Where this record came from and when it was last checked.

Reference
AlexaTM 20B: Few-Shot Learning Using a Large-Scale Multilingual Seq2Seq Model
Last updated
25 May 2026

What the numbers mean

Where it came from

AlexaTM 20B was published by Amazon, in United States of America, in August 2022. industry is the category the publisher falls under.

It works in Language, and is recorded as doing language modeling, Translation, Question answering.

Its weights were never published, so it can only be reached through its provider. No graphics card changes that.

How it was trained

Producing it required around 2 × 10²³ FLOP of arithmetic, on NVIDIA A100, which is a statement about the training budget rather than about inference.

Around 1,319,000,000,000 tokens went into training it.

Its inclusion criterion is sOTA improvement.

Answers

AlexaTM 20B — common questions

01

Who created AlexaTM 20B?

AlexaTM 20B was published by Amazon, based in United States of America, categorised as industry.

02

When was AlexaTM 20B released?

AlexaTM 20B was published in August 2022. Capability per parameter has improved considerably since, so a newer model of the same size is often the better use of the same hardware.

03

What is AlexaTM 20B used for?

AlexaTM 20B works in Language, and is recorded as handling language modeling, Translation, Question answering. A model can carry several of each, so these are the areas it was built for rather than a limit on what it will attempt.

04

How much compute was used to train AlexaTM 20B?

Around 2 × 10²³ FLOP, on NVIDIA A100. That measures what producing the model cost and says nothing about how quickly it answers once trained — inference speed comes from memory bandwidth, not from the training budget.

05

What GPU do I need to run AlexaTM 20B?

None. AlexaTM 20B is a closed model — its weights were never published, so it cannot be downloaded or run on your own hardware at any price. It is reachable only through its provider.

06

Is AlexaTM 20B open source?

No. AlexaTM 20B has not had its weights published, so it exists only as a service controlled by its owner.

07

How many parameters does AlexaTM 20B have?

AlexaTM 20B has 19.8B parameters. See Table 1 on p.3 of the paper. That figure is the total, and it is what decides how much memory the model needs — roughly half a gigabyte per billion at the compression most people use.

Source

Original publication

Record last updated 25 May 2026

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