> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hologram.io/llms.txt
> Use this file to discover all available pages before exploring further.

# What are typical data transmission speeds?

> Expected cellular speeds for IoT devices and considerations for Cat-M1 and NB-IoT.

Cellular data speeds vary by coverage, tower load, radio technology, and device configuration. Hologram SIMs can access 2G, 3G, 4G/LTE, and LTE-M where available.

## Cat-M1 speeds

Cat-M1 is designed for lower power and lower bandwidth IoT links. Typical uplink/downlink is around 375 kbit/s in half-duplex, suitable for small to medium payloads.

## NB-IoT

Optimized for low-bandwidth tasks (sensors, small telemetry, and infrequent messages).

## Profile performance

For U.S. latency/throughput guidance, see: [Profile performance in the U.S.](/guides/sims/profile-performance-in-the-us)

## Related actions

<Card title="Find coverage and rates" icon="map" href="/dashboard/billing/coverage-explorer" horizontal>
  Explore coverage and pricing by country
</Card>

<Card title="Choose a data plan" icon="server" href="/dashboard/billing/data-plans" horizontal>
  Review and select your data plan options
</Card>

<Card title="Profile performance in the U.S." icon="gauge-high" href="/guides/sims/profile-performance-in-the-us" horizontal>
  Learn about latency and throughput metrics
</Card>