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AI TRAINING CALCULATOR

For your model's next step,
how much GPU memory is needed?

Compare the capacity needs of inference and LoRA fine-tuning, with item-by-item estimates for model weights, KV Cache, and GPU count.

MEMORY ESTIMATE
21.2Estimated total GPU memory · GB
Model Weights
16.0 GB
KV Cache
0.5 GB
Activations
3.2 GB
Framework reserve
1.5 GB

Illustrative figures for capacity planning, not measured results.

GPU CAPACITY

How many GPUs do you need?

This table is based only on total GPU memory. Multi-card configurations still require model sharding plus framework and interconnect support, and are not guaranteed to run directly.

GPUGPU memory / cardMinimum cardsTotal capacityCapacity usage
B300Deliverable288 GB1288 GB7.4%
B200180 GB1180 GB11.8%
H200Deliverable141 GB1141 GB15.1%
H100 NVL94 GB194 GB22.6%
A100 80GB80 GB180 GB26.5%
H100 SXM5Deliverable80 GB180 GB26.5%
L40S48 GB148 GB44.2%
A100 40GB40 GB140 GB53.1%
RTX 409024 GB124 GB88.5%
ASSUMPTIONS

State the assumptions behind the estimate

View formulas and limitations

GB uses decimal units. Weights = parameters × precision bytes; KV Cache = 2 × layers × KV Heads × Head Dim × context length × Batch Size × 2 bytes. The cache is fixed at FP16.

Inference activation is estimated at 20% of the weights; for LoRA fine-tuning it is 25% with Gradient Checkpointing enabled and 60% with it disabled. LoRA Rank 8/16/32/64 corresponds to estimated ratios of 2%/4%/6%/8%, and LoRA state = parameters × ratio × 2 × 13 bytes. The framework reserve is fixed at 1.5 GB. Fine-tuning mode also includes the KV Cache, which is not the same as cache behavior during actual training.

A custom model's architecture is approximated from its parameter count and cannot replace the model configuration file.

The LoRA ratio and activation are both rough estimates. Actual usage depends on the framework, model architecture, quantization, and optimizer. INT8/INT4 fine-tuning requires a compatible quantized LoRA toolchain. This tool does not estimate training time or run training jobs.

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Bring your estimate to the sales team and discuss specs