LTE Throughput Calculator
Compute LTE peak downlink throughput from bandwidth, MIMO layers, modulation, code rate, carrier aggregation and duplex mode. Use UE category presets to replicate 3GPP reference throughputs (Cat 4 through Cat 20).
Applies typical layers, modulation, CA and 20 MHz BW.
Throughput vs. bandwidth (same layers / modulation)
| Bandwidth | Nprb | Throughput (Mbps) |
|---|---|---|
| 5 MHz | 25 | 35.2 |
| 10 MHz | 50 | 70.3 |
| 20 MHz | 100 | 140.6 |
About LTE throughput
LTE peak downlink throughput is driven by how many resource elements (REs) you can fill per second and how many bits each RE carries. A 20 MHz LTE carrier has 100 PRBs. Each PRB is 12 subcarriers wide, and a 1 ms subframe contains 14 OFDM symbols with normal CP. That gives 100 × 12 × 14 × 1000 = 16.8 million REs/s per layer. Multiply by the modulation order (2 for QPSK, 4 for 16QAM, 6 for 64QAM, 8 for 256QAM), the code rate (up to ~0.93), the number of MIMO layers, the number of aggregated carriers, and — for TDD — the fraction of subframes allocated to downlink.
UE categories (Cat 4, 6, 9, 12, 16, 20) represent published 3GPP peak rates. Cat 4 is the classic single-carrier 2×2 MIMO 64QAM 150 Mbps phone. Cat 16 adds 4×4 MIMO plus 256QAM plus 4 CC for gigabit LTE. Cat 20 reaches 2 Gbps with 5 CC. Real-world throughput is always lower due to channel quality, scheduling overhead and cell load — subtracting the typical 25% overhead gives a more realistic MAC-layer peak.
Related tools
How to calculate LTE peak throughput
- Enter the bandwidth. Select the channel bandwidth (1.4 to 20 MHz), which fixes the resource-block count.
- Set MIMO layers. Choose the number of spatial layers (SISO, 2×2, 4×4) to model.
- Choose modulation. Pick QPSK, 16QAM, 64QAM or 256QAM to set the bits per symbol.
- Add carrier aggregation. Specify how many component carriers are combined; the tool sums their contributions.
- Apply the UE category. Select the UE category so the result is clamped to a realistic peak, then read the Mbps.
Frequently asked questions
- How do you work out LTE peak throughput?
- The clean way is resource-element counting: a 20 MHz carrier has 100 RBs, each RB carries 12 subcarriers × 7 symbols per 0.5 ms slot, and you multiply the usable REs per second by the bits per symbol and the code rate, then by the number of MIMO layers. Subtract the REs taken by reference signals, PDCCH, PSS/SSS and PBCH. For a quick sanity check, 20 MHz / 2×2 MIMO / 64QAM lands near 150 Mbps downlink.
- What does the UE category limit?
- UE Category caps the transport-block bits the modem can process per TTI and the supported MIMO layers, so it sets the real ceiling regardless of how much spectrum you give it. Cat 4 tops out around 150 Mbps DL, Cat 6 around 300 Mbps (two-carrier CA), and the higher categories scale with more aggregated carriers and layers. Always check the category before trusting a raw bandwidth calculation.
- How does carrier aggregation change the number?
- Each aggregated component carrier adds its own throughput, so peak rate is the sum across carriers, not a single 20 MHz figure. Three 20 MHz carriers with 2×2 MIMO and 64QAM approach 450 Mbps. The aggregate is still bounded by the UE category, so a low-category device will not reach the sum even if the network offers the carriers.
Get the next 5G/LTE engineering deep-dive in your inbox
These calculators give you the number — the weekly digest gives you the theory. One technical breakdown every Tuesday, plus first access to new tools. Unsubscribe in one click.
Calculator gave you the answer? Learn the theory in 7 days, free.
Full Pro access — 142+ hands-on exercises, 20+ troubleshooting scenarios, 21 certifications, TelcoMentor AI coach. No credit card. See pricing on /pricing.
- No credit card
- Full Pro access
- 21 verifiable certs
- TELCOMA since 2009