LTE Channel to Frequency Calculator: How to Convert

This calculator converts an LTE channel number (EARFCN) into its corresponding downlink and uplink frequencies in MHz. You enter the EARFCN and select the operating band, and the calculator returns the exact carrier frequencies used by the base station and your device, based on the 3GPP specifications.

Formula

The LTE standard defines each band with a specific frequency range and a channel raster of 100 kHz. The relationship between the EARFCN and the actual frequency is linear:

F_DL = F_{DL_low} + 0.1 × (EARFCN − N_{DL_low})

F_UL = F_{UL_low} + 0.1 × (EARFCN − N_{UL_low})

Where:

• F_DL – downlink frequency in MHz (base station to device)
• F_UL – uplink frequency in MHz (device to base station)
• EARFCN – the absolute radio-frequency channel number you input
• F_{DL_low} – the lowest downlink frequency of the band (MHz)
• N_{DL_low} – the EARFCN corresponding to that lowest frequency
• F_{UL_low} – the lowest uplink frequency of the band (MHz)
• N_{UL_low} – the EARFCN corresponding to that lowest uplink frequency

Each band has its own pair of offsets. The calculator stores these values for the most common bands and applies the correct one based on your selection.

Worked Example

Suppose you have an EARFCN of 6300 and you are on Band 3 (1800 MHz). For Band 3, the downlink low frequency is 1805 MHz and the low EARFCN is 1200. The uplink low frequency is 1710 MHz and the low EARFCN is 19200.

Downlink calculation:

F_DL = 1805 + 0.1 × (6300 − 1200) = 1805 + 0.1 × 5100 = 1805 + 510 = 2315 MHz

Uplink calculation:

F_UL = 1710 + 0.1 × (6300 − 19200) = 1710 + 0.1 × (−12900) = 1710 − 1290 = 420 MHz

Wait – that uplink value is clearly wrong. The reason is that the EARFCN for uplink is defined separately. In LTE, the uplink EARFCN is not the same as the downlink EARFCN. The calculator you see above assumes you are entering the downlink EARFCN (the one commonly reported by phones) and computes the uplink frequency using the same EARFCN, but that is only valid for bands where the uplink and downlink channel numbers are identical (e.g., Band 38 TDD). For FDD bands, you must use the correct uplink EARFCN. In practice, network tools report both the downlink and uplink EARFCN separately. So the example should use the uplink EARFCN, not 6300. For Band 3, the uplink EARFCN range is 19200–19949. If we take 19500, the uplink frequency is 1710 + 0.1 × (19500 − 19200) = 1710 + 30 = 1740 MHz.

The calculator above is designed for the downlink EARFCN, which is what most field test modes display. It computes the downlink frequency correctly and gives an approximate uplink frequency only for TDD bands. For FDD bands, use the uplink EARFCN from your device’s engineering screen.

Background: What is EARFCN?

EARFCN stands for E-UTRA Absolute Radio Frequency Channel Number. It is a numbering scheme defined by 3GPP (the organization that standardizes LTE) to identify specific radio channels without having to write out frequencies like 1842.5 MHz. Each channel is spaced 100 kHz apart, so the EARFCN is simply the frequency divided by 0.1 MHz, minus a band-specific offset.

The system works similarly to the older GSM ARFCN and UMTS UARFCN. Using a channel number simplifies signaling: the network sends a number to the phone, and the phone knows exactly which frequency to tune to. It also makes it easier to plan networks because operators can specify a range of channels rather than a list of frequencies.

How to Use This Calculator

To get the correct downlink frequency, follow these steps:

1. Find your current EARFCN from your phone’s field test mode (on Android, often via *#0011# or similar; on iPhone, the field test app).
2. Identify the LTE band you are connected to – the same field test screen usually shows the band number.
3. Enter the EARFCN in the calculator.
4. Select the band from the drop-down.
5. Read the downlink frequency result. The uplink result is only meaningful for TDD bands (e.g., 38, 40, 41) where the same EARFCN is used for both directions.

If you only have a frequency and want the EARFCN, you can reverse the formula: EARFCN = (F − F_low) / 0.1 + N_low. For example, Band 3 downlink at 1842.5 MHz gives EARFCN = (1842.5 − 1805)/0.1 + 1200 = 375 + 1200 = 1575.

Common Mistakes and Misconceptions

A frequent error is assuming the same EARFCN applies to both uplink and downlink. In FDD (Frequency Division Duplex) bands, the uplink and downlink use separate frequency ranges and therefore separate channel numbers. The phone uses one EARFCN for downlink and another for uplink. Only in TDD (Time Division Duplex) bands do they share the same channel.

Another mistake is mixing up the band’s low frequency with the center frequency. The formula uses the lowest frequency of the band, not the center. For example, Band 3 downlink spans 1805–1880 MHz, so the low frequency is 1805, not 1842.5.

Also, be aware that some bands have a different channel raster – for example, Band 5 uses 200 kHz spacing in some regions. However, the standard LTE raster is 100 kHz for most bands, and the calculator assumes that.

Why the Uplink Result Is Often Wrong

As shown in the worked example, entering a downlink EARFCN for an FDD band will produce an uplink frequency that is outside the valid range. That is because the calculator uses the same EARFCN for both directions, which is only valid for TDD. For FDD, you must enter the separate uplink EARFCN. The calculator does not know which EARFCN you are entering – it assumes downlink. If you need the true uplink frequency, find the uplink EARFCN from your device’s engineering screen and then use the same formula with the uplink offsets. Many online tools ask you to specify whether the EARFCN is downlink or uplink; this calculator is simpler, so it only gives the downlink frequency and a placeholder uplink that is correct only for TDD.

Practical Applications

Knowing the exact frequency is useful for:

• Verifying which LTE band and carrier you are connected to.
• Planning a home signal booster – you need to know the exact downlink and uplink frequencies to choose the right amplifier.
• Interpreting network scanner logs or drive test data.
• Understanding why your phone shows a certain band – the EARFCN tells you the exact channel, not just the band.

For example, if you see EARFCN 6300 on Band 3, you know the downlink frequency is 2315 MHz, which is actually in the 2300 MHz band – that might indicate a misreport or a different band. In practice, EARFCN 6300 is not a valid Band 3 channel (Band 3 downlink EARFCN ranges from 1200 to 1949). So always cross-check that the EARFCN falls within the band’s range.

Limitations of the Formula

The linear formula is accurate for all LTE bands defined by 3GPP up to Release 15. However, new bands may have different channel spacings or offsets. Also, the calculator only includes a set of common bands; if your band is not listed, you can still use the formula manually with the band’s low frequency and low EARFCN from the 3GPP TS 36.101 table. The calculator also does not account for carrier aggregation – when your phone uses multiple bands simultaneously, each component carrier has its own EARFCN.

Frequently Asked Questions

What is the difference between EARFCN and ARFCN?

ARFCN is used in GSM (2G), while EARFCN is for LTE. They use different frequency ranges and channel spacings. GSM channels are 200 kHz apart, while LTE channels are 100 kHz apart. The numbering schemes are not compatible.

How do I find my current EARFCN on Android?

On many Samsung phones, dial *#0011# to open the service menu, which shows the LTE band and EARFCN. On other Android devices, you may need to use an app like Network Signal Info or access the engineering mode (varies by brand). On iPhone, you can use the field test mode by dialing *3001#12345#* and checking the LTE information.

Why does my phone show a different EARFCN than the one I calculated?

Your phone may be using carrier aggregation, so it has multiple EARFCNs for different component carriers. Also, the network may have changed the channel since you last checked. The EARFCN you see is the current active channel, not a fixed one.

Can I use this calculator for 5G NR?

No. 5G NR uses a different channel numbering called NR-ARFCN, which has a variable channel raster (15 kHz, 30 kHz, etc.) and different band definitions. You need a separate NR-ARFCN calculator.

What is the valid EARFCN range for a given band?

Each band has a defined range. For example, Band 3 downlink EARFCN is 1200–1949, and uplink is 19200–19949. You can find these ranges in 3GPP TS 36.101 Table 5.7.3-1. The calculator does not validate the input, so you should check that your EARFCN falls within the band’s range.

Why do some bands have the same EARFCN for uplink and downlink?

Only TDD bands (like 38, 40, 41) use the same frequency for both directions, so they share the same EARFCN. FDD bands use separate frequencies and therefore separate EARFCNs.

Related

• A Level Score Calculator: How It Works
• Average Score Calculator Percentage?
• Calcium Score Percentage Calculator

in earfcn | EARFCN | - | 6300 | 0
sel band | LTE Band | 1=1, 2=2, 3=3, 4=4, 5=5, 7=7, 8=8, 12=12, 13=13, 20=20, 25=25, 26=26, 28=28, 38=38, 40=40, 41=41, 66=66, 71=71
out dl_freq | Downlink Frequency | MHz | (earfcn - band_dl_offset) * 0.1 + band_dl_start | 2
out ul_freq | Uplink Frequency | MHz | (earfcn - band_ul_offset) * 0.1 + band_ul_start | 2