What Is SUN on TRON and How to Convert It to TRX

SUN is the smallest unit of TRX: 1 TRX = 1,000,000 SUN, so 1 SUN = 0.000001 TRX. To convert SUN to TRX, divide by 1,000,000, which is the same as moving the decimal point six places to the left: 6,428,500 SUN is 6.4285 TRX. The ratio is fixed by the protocol and never changes.

Fees per unit are quoted in SUN because they are tiny: burning one unit of energy costs 100 SUN, or 0.0001 TRX, as of Oct 19, 2026. Below: real TRON values in both units, how to read a receipt, and how to turn a price “per unit of energy” into TRX per transfer.

What SUN is

The TRON developer documentation puts it plainly: “TRX has a smaller denomination called sun”, and “most smart contract and API interactions are calculated in sun” (TRX denominations). The docs write the unit in lowercase and keep uppercase SUN for the separate SUN.io token; wallets and this blog usually write the unit as SUN, and in this article SUN always means the unit.

TRX has six decimal places, so every TRX amount is a whole number of SUN. The network never stores “0.5 TRX”. It stores 500,000 SUN. That is why raw data looks strange at first:

• the TronGrid API returns balances in SUN: a balance of 25,000,000 means 25 TRX;
• transaction receipts report burned fees in SUN: energy_fee, net_fee and the total fee;
• chain parameters such as getEnergyFee and getTransactionFee are set in SUN.

TronScan and wallets usually convert to TRX for display, so the same fee appears as 6.4285 in one place and 6428500 in another. The smallest possible TRX transfer is 1 SUN; on Oct 19, 2026 we saw a transfer of 2 SUN, that is 0.000002 TRX.

Two things SUN is not

It is not the SUN token. There is also a TRC-20 token called SUN (contract TSSMHYeV2uE9qYH95DqyoCuNCzEL1NvU3S, named SunToken on chain). The token has a market price that moves. The unit has no market price at all: it is always one millionth of a TRX. If you searched “sun to trx” because of the token, you need a price quote, not a conversion.

It is not the smallest unit of USDT. USDT on TRON also has six decimal places (the contract’s decimals() returns 6), so raw token amounts look similar. A USDT Approval event we saw on Oct 19, 2026 carried a raw value of 11833518, which means 11.833518 USDT. That number is in the token’s own base units, not in SUN, and has nothing to do with TRX.

How to convert SUN to TRX

Two formulas cover everything:

TRX = SUN / 1,000,000

SUN = TRX × 1,000,000

A quick reference:

SUN	TRX	Where you meet this amount
1	0.000001	smallest possible transfer
100	0.0001	burn price of 1 unit of energy
1,000	0.001	burn price of 1 unit of bandwidth
345,000	0.345	bandwidth burned for a USDT transfer
1,000,000	1	one TRX
6,428,500	6.4285	energy burned for a standard USDT transfer
100,000,000	100	a common fee limit for contract calls

By hand: count six digits from the right and put the point there, padding with zeros if needed: 345 SUN is 0.000345 TRX.

TRON values in SUN and TRX as of Oct 19, 2026

These are the network parameters you are most likely to meet, read from the public chain parameters on Oct 19, 2026 (the same list is shown on the TronScan committee page):

What it is	Parameter	SUN	TRX
Burn price of 1 unit of energy	getEnergyFee	100	0.0001
Burn price of 1 unit of bandwidth	getTransactionFee	1,000	0.001
Activating a new address	getCreateNewAccountFeeInSystemContract	1,000,000	1
Bandwidth for that activation, if burned	getCreateAccountFee	100,000	0.1
Adding a memo (note) to a transaction	getMemoFee	1,000,000	1
Extra fee for a multi-signature transaction	getMultiSignFee	1,000,000	1
Changing account permissions	getUpdateAccountPermissionFee	100,000,000	100
Issuing a TRC-10 token	getAssetIssueFee	1,024,000,000	1,024
Highest fee limit a transaction may set	getMaxFeeLimit	15,000,000,000	15,000

The first two lines decide what an ordinary transfer costs. Activation is explained in how to activate a TRON address, bandwidth in TRON bandwidth cost.

The burn price of energy has not always been 100 SUN. Since 2020 it has gone from 40 SUN up to 420 SUN and back down to 100 SUN after Proposal #104 in August 2025; the full list of votes is in what is TRON energy. As of Oct 19, 2026 no proposal after #107 had been approved, and the value is still 100.

Reading a receipt in SUN

Every transaction receipt states its charges in SUN. Here are three real ones from Oct 17-19, 2026, converted:

Transaction	Field in the receipt	SUN	TRX
USDT transfer, no energy on the sender	energy_fee	6,428,500	6.4285
the same transfer	net_fee (bandwidth)	345,000	0.345
Swap of USDT for TRX on a DEX	fee (total)	17,205,300	17.2053
USDT approve with own energy	fee_limit set by the sender	100,000,000	100

The first transfer burned 64,285 units of energy at 100 SUN each: 64,285 × 100 = 6,428,500 SUN. Add 345,000 SUN for bandwidth and the total is 6,773,500 SUN, or 6.7735 TRX.

The last line is a ceiling, not a charge. The sender allowed the network to burn up to 100 TRX, but the approve was covered by energy and bandwidth already on the address, so nothing was burned.

How to read energy prices quoted in SUN

Energy is priced per unit, and a per-unit price in SUN means nothing until you multiply it by the energy a transaction uses. The general rule:

TRX per transfer = price per unit in SUN × energy used / 1,000,000

The amount of energy depends on the transaction. A standard USDT transfer uses 64,285, a transfer to an address with no USDT uses 130,285 (this site rounds them to 65,000 and 131,000). For other transaction types, see how much energy each transaction type uses. The full calculation of what to keep on the balance, including bandwidth and partial energy, is in how much TRX you need to send USDT; here we only convert units.

Here is the same conversion for the burn price and for the current rental rate on Nov 12, 2026, 26 SUN per unit of energy for 1 hour:

Price per unit	64,285 energy	65,000 energy	131,000 energy
100 SUN (network burn)	6,428,500 SUN = 6.4285 TRX	6,500,000 SUN = 6.5 TRX	13,100,000 SUN = 13.1 TRX
26 SUN (rental)	1,671,410 SUN = 1.67141 TRX	1,690,000 SUN = 1.69 TRX	3,406,000 SUN = 3.406 TRX

The rental rate changes, and the exact price is shown in the service before you pay, and reference prices are on the pricing page.

It also works backwards: 1.69 TRX for 65,000 energy is 1,690,000 / 65,000 = 26 SUN per unit.

Four checks before you compare any two prices:

1. Per unit or per transfer. “26” and “1.69” can be the same price written two ways.
2. Which energy amount. 65,000 energy does not cover a transfer to a new address.
3. Which period. Compare rental prices for the same period only.
4. What is left out. Energy prices never include bandwidth: once the free 600 units are used up, a USDT transfer adds 345,000 SUN (0.345 TRX).

A shortcut: the ratio of two per-unit prices is the ratio of the costs. The current 26 SUN against the 100 SUN burn price means the energy part costs 26% of burning, whatever the amount.

How to convert any TRON number in three steps

1. Find the unit. API responses, receipts and chain parameters are in SUN. Wallet screens and TronScan pages usually show TRX. If a fee looks a million times too large, it is in SUN.
2. Divide by 1,000,000 to get TRX, or multiply to go the other way. For a price per unit of energy or bandwidth, multiply by the number of units first.
3. Check the current parameter. The burn prices of 100 and 1,000 SUN are as of Oct 19, 2026. They change only by a vote, but they do change, so look them up before a large calculation.

FAQ

How many SUN are in 1 TRX? 1,000,000. One SUN is 0.000001 TRX. The ratio is part of the protocol and does not move.

How much is 100 SUN in TRX? 0.0001 TRX. That is the burn price of one unit of energy as of Oct 19, 2026.

Why does the API show my balance as a huge number? Because it is in SUN. Divide by 1,000,000: a balance of 1,500,000,000 is 1,500 TRX. More answers are in the FAQ.