---
title: Datacenter AI Capacity Explorer
description: Size AI accelerator capacity from facility power, PUE, racks, cooling, density, TDP and MFU without deriving inference throughput from FLOPs.
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<div class="s5-landing s5-tool-page s5-datacenter-capacity" data-s5-datacenter-ai-capacity data-locale="en">
<section class="s5-page-intro">
  <div class="s5-eyebrow">Tools · Infrastructure · 17</div>
  <h1>Find what actually limits an AI datacenter.</h1>
  <p>Set the total facility power envelope, PUE, rack count, physical density and cooling. The explorer calculates how many accelerators can be active while keeping physical capacity, training throughput and inference throughput as separate questions.</p>
</section>
<div class="s5-tool-summary-strip"><div><small>Facility</small><strong>total MW → IT</strong></div><div><small>Rack</small><strong>power + cooling</strong></div><div><small>Training</small><strong>peak × MFU</strong></div><div><small>Inference</small><strong>measurement only</strong></div></div>

<div class="s5-tool-workbench">
<form class="s5-tool-controls" aria-label="Datacenter assumptions" onsubmit="return false">
<section class="s5-tool-controls__section"><h2>Facility</h2><div class="s5-tool-field"><label for="s5-dc-fac-en">Total facility power <span>MW</span></label><input id="s5-dc-fac-en" data-field="facilityMW" type="number" min="0.01" step="0.5" value="10" inputmode="decimal" /><small>Includes IT and facility support. The IT budget is approximated from representative PUE.</small></div><div class="s5-tool-field"><label for="s5-dc-pue-en">Representative PUE</label><input id="s5-dc-pue-en" data-field="pue" type="number" min="1" max="5" step="0.01" value="1.2" inputmode="decimal" /><small>PUE is an energy ratio; applying it to power assumes it represents this operating point.</small></div><div class="s5-tool-field"><label for="s5-dc-res-en">IT capacity reserve <span>%</span></label><input id="s5-dc-res-en" data-field="facilityReservePct" type="number" min="0" max="95" step="1" value="10" inputmode="decimal" /><small>Headroom intentionally left unallocated by the calculated workload.</small></div></section>
<section class="s5-tool-controls__section"><h2>Racks</h2><div class="s5-tool-field"><label for="s5-dc-racks-en">Available racks <span>units</span></label><input id="s5-dc-racks-en" data-field="racks" type="number" min="1" step="1" value="200" inputmode="numeric" /></div><div class="s5-tool-field"><label for="s5-dc-installed-en">Installed accelerators per rack <span>units</span></label><input id="s5-dc-installed-en" data-field="installedPerRack" type="number" min="1" step="1" value="64" inputmode="numeric" /></div><div class="s5-tool-field"><label for="s5-dc-rack-power-en">Per-rack IT electrical limit <span>kW</span></label><input id="s5-dc-rack-power-en" data-field="rackPowerKW" type="number" min="0.1" step="1" value="60" inputmode="decimal" /></div><div class="s5-tool-field"><label for="s5-dc-rack-cooling-en">Per-rack IT heat-removal capacity <span>kW</span></label><input id="s5-dc-rack-cooling-en" data-field="rackCoolingKW" type="number" min="0.1" step="1" value="50" inputmode="decimal" /><small>Use the effective thermal limit of the rack or the cooling system serving it.</small></div></section>
<section class="s5-tool-controls__section"><h2>Hardware and compute</h2><div class="s5-tool-field"><label for="s5-dc-preset-en">Accelerator</label><select id="s5-dc-preset-en" data-field="preset"></select><small data-output="hardware-note">—</small></div><div class="s5-tool-field"><label for="s5-dc-power-en">Average accelerator power <span>% of TDP</span></label><input id="s5-dc-power-en" data-field="powerUtilizationPct" type="number" min="0.1" max="100" step="1" value="85" inputmode="decimal" /></div><div class="s5-tool-field"><label for="s5-dc-other-en">Associated non-accelerator IT <span>% of accelerator power</span></label><input id="s5-dc-other-en" data-field="otherITPct" type="number" min="0" max="1000" step="1" value="15" inputmode="decimal" /><small>Approximate CPU, memory, network and storage attached to each accelerator.</small></div><div class="s5-tool-field"><label for="s5-dc-mfu-en">Training MFU <span>% of dense peak</span></label><input id="s5-dc-mfu-en" data-field="mfuPct" type="number" min="0.1" max="100" step="1" value="45" inputmode="decimal" /></div></section>
<section class="s5-tool-controls__section"><h2>Optional inference mapping</h2><div class="s5-tool-field"><label for="s5-dc-toks-en">Measured sustained throughput <span>output tokens/s per accelerator</span></label><input id="s5-dc-toks-en" data-field="measuredTokensPerSecPerAccelerator" type="number" min="0" step="10" value="0" inputmode="decimal" /><small>0 disables the estimate. Enter a measurement from your model, runtime, batching policy and target SLO; it is not inferred from FLOPs.</small></div><div class="s5-tool-field"><label for="s5-dc-out-en">Average completion length <span>tokens</span></label><input id="s5-dc-out-en" data-field="avgOutputTokens" type="number" min="1" step="10" value="500" inputmode="decimal" /></div></section>
<details><summary>Advanced accelerator assumptions</summary><section class="s5-tool-controls__section"><div class="s5-tool-field"><label for="s5-dc-peak-en">Dense BF16 peak <span>TFLOP/s</span></label><input id="s5-dc-peak-en" data-field="peakTflops" type="number" min="0.001" step="1" value="989.5" inputmode="decimal" /></div><div class="s5-tool-field"><label for="s5-dc-tdp-en">Maximum TDP <span>W</span></label><input id="s5-dc-tdp-en" data-field="tdpW" type="number" min="1" max="5000" step="10" value="700" inputmode="decimal" /></div></section></details>
<section class="s5-tool-controls__section"><div class="s5-tool-actions"><button class="s5-tool-action" type="button" data-action="share">Copy scenario</button><button class="s5-tool-action" type="button" data-action="json">Export JSON</button><button class="s5-tool-action" type="button" data-action="reset">Reset</button></div><p class="s5-tool-feedback" data-s5-tool-feedback hidden aria-live="polite"></p></section>
</form>

<section class="s5-tool-results">
<div class="s5-section-head s5-section-head--with-copy"><div><div class="s5-eyebrow">Result</div><h2>Capacity is the minimum of independent limits.</h2></div><p data-output="interpretation" aria-live="polite">—</p></div>
<div class="s5-datacenter-capacity-kpis"><div><small>Active accelerators</small><strong data-output="active-accelerators">—</strong><span>maximum simultaneous</span></div><div><small>Bottleneck</small><strong data-output="bottleneck">—</strong><span>limiting constraint</span></div><div><small>Facility draw</small><strong data-output="facility-draw">—</strong><span>with PUE applied</span></div><div><small>Training compute</small><strong data-output="training-throughput">—</strong><span>dense peak × MFU</span></div></div>
<section class="s5-dc-panel"><div class="s5-dc-panel__head"><h3>Four limits on the same fleet</h3><p>Each bar shows how many accelerators that constraint would support on its own. The publishable capacity is the smallest value, so available power is never mistaken for physical or cooling capacity.</p></div><div class="s5-dc-constraints" data-output="constraint-bars"></div></section>
<div class="s5-dc-detail-grid"><section><h3>Facility</h3><p>Usable IT capacity: <strong data-output="usable-it">—</strong></p><p>IT reserve: <strong data-output="reserved-it">—</strong></p><p>Total-power headroom: <strong data-output="facility-headroom">—</strong></p><p>Total-envelope utilization: <strong data-output="facility-utilization">—</strong></p></section><section><h3>Rack</h3><p>Maximum active per rack: <strong data-output="max-per-rack">—</strong></p><p>IT load at that maximum: <strong data-output="rack-it">—</strong></p><p>Electrical headroom per rack: <strong data-output="rack-power-headroom">—</strong></p><p>Thermal headroom per rack: <strong data-output="rack-cooling-headroom">—</strong></p></section><section><h3>Training</h3><p>Active-fleet dense BF16 peak: <strong data-output="peak-compute">—</strong></p><p>Sustained compute at MFU: <strong data-output="training-throughput">—</strong></p><p>Sustained compute per day: <strong data-output="training-day">—</strong></p></section><section><h3>Physical density</h3><p>Installed slots that can actually be used: <strong data-output="slot-utilization">—</strong></p><p>Low utilization here does not imply poor efficiency. Power or cooling may simply bind before physical space does.</p></section></div>
<section class="s5-dc-inference"><h3>Inference: use a serving measurement, not peak FLOPs</h3><p data-output="inference-note">—</p><div class="s5-dc-inference__metrics"><div><small>Aggregate throughput</small><strong data-output="inference-tokens">—</strong></div><div><small>Approximate completions</small><strong data-output="inference-completions">—</strong></div></div></section>
</section></div>

<section class="s5-section"><div class="s5-section-head"><div><div class="s5-eyebrow">Method</div><h2>Keep facility, rack and service separate.</h2></div></div><div class="s5-dc-method"><div><strong>1 · Facility</strong><p>Total facility power is divided by a representative PUE to approximate IT capacity. The operational reserve is then removed.</p></div><div><strong>2 · Rack</strong><p>Each accelerator adds average GPU power plus associated IT. That footprint is checked independently against installed slots, rack electrical power and rack heat-removal capacity.</p></div><div><strong>3 · Compute and serving</strong><p>Training uses dense BF16 peak × MFU. Inference is calculated only when you enter measured sustained throughput from your stack; FLOPs are never converted into tokens/s.</p></div></div></section>
<section class="s5-section"><div class="s5-note-feature"><div><div class="s5-eyebrow">Limits</div><h2>This is a capacity model, not an MEP design or a serving benchmark.</h2><p>PUE is an energy ratio and can change with load and climate. TDP is not average power. The associated-IT approximation is linear even though CPU, network and storage do not always scale that way. Thermal capacity must come from the actual rack and cooling design. MFU depends on workload and software. Inference throughput depends on model, precision, context, batching, runtime and SLO, which is why this explorer only aggregates a throughput measurement that you provide.</p><p><a href="/en/tools/training-compute-energy/">Compare with the Training Compute / Energy Estimator →</a></p></div><div class="s5-note-feature__meta"><a href="https://www.nvidia.com/en-us/data-center/h100/">NVIDIA H100</a><br /><a href="https://www.nvidia.com/en-us/data-center/h200/">NVIDIA H200</a><br /><a href="https://www.nvidia.com/en-us/data-center/hgx/">NVIDIA HGX B200</a><br /><a href="https://docs.nvidia.com/dgx/dgxb200-user-guide/introduction-to-dgxb200.html">DGX B200 · power</a><br /><a href="https://docs.nvidia.com/dgx-pdf/nvidia-dgx-superpod-data-center-best-practices-with-dgx-b200.pdf">DGX B200 · rack</a><br /><a href="https://www.thegreengrid.org/node/372">The Green Grid · PUE</a><br />Sources reviewed: 2026-08-22</div></div></section>
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