> For the complete documentation index, see [llms.txt](https://docs.tronsave.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tronsave.io/developers/api-reference/buy-resources/signed-tx/get-signed-transaction.md). # Get Signed Transaction This is **Step 2** of the [Buy with Signed Transaction](/developers/api-reference/buy-resources/signed-tx.md) flow. After [Step 1 — Estimate TRX](/developers/api-reference/buy-resources/signed-tx/estimate-trx.md) returns an `estimateTrx` (the cost of the buy order in SUN), you produce a signed transfer transaction that pays that amount from the buyer's wallet to the TronSave fund address. You then submit it in [Step 3 — Create Order](/developers/api-reference/buy-resources/signed-tx/create-order.md). You can do this two ways: sign the transaction yourself ([Option 1](#option-1-write-your-own-function)), or let the TronSave API sign it for you ([Option 2](#option-2-use-the-tronsave-api)). ## Option 1: Write your own function Using the `estimateTrx` value from [Step 1](/developers/api-reference/buy-resources/signed-tx/estimate-trx.md), build a TRX transfer transaction with `transactionBuilder` that sends an amount equal to `estimateTrx` from the buyer's address to the TronSave fund address, then sign it with the buyer's private key: ```tsx const dataSendTrx = await tronWeb.transactionBuilder.sendTrx('TRONSAVE_FUND_ADDRESS', estimate_trx, 'BUYER_ADDRESS') const signed_tx = await tronWeb.trx.sign(dataSendTrx, 'PRIVATE_KEY'); ``` {% hint style="info" %} * `BUYER_ADDRESS` — the buyer's public address. * `PRIVATE_KEY` — the buyer's private key. * `TRONSAVE_FUND_ADDRESS` — the TronSave fund address (see below). {% endhint %} **TronSave fund address (`TRONSAVE_FUND_ADDRESS`):** {% tabs %} {% tab title="MAINNET" %} ``` TWZEhq5JuUVvGtutNgnRBATbF8BnHGyn4S ``` {% endtab %} {% tab title="Nile (for testing)" %} {% hint style="warning" %} This fund address is for testing purposes only on the TRON Nile network. {% endhint %} ``` TATT1UzHRikft98bRFqApFTsaSw73ycfoS ``` {% endtab %} {% endtabs %} The result `signed_tx` is then passed to [Step 3 — Create Order](/developers/api-reference/buy-resources/signed-tx/create-order.md). ## Option 2: Use the TronSave API **`POST`** **`https://api.tronsave.io/v2/signed-tx`** This endpoint builds and signs the transfer transaction for you, given the buyer's address, private key, and the `estimateTrx` from Step 1. {% hint style="info" %} **Rate limit:** 15 requests per 1 second. {% endhint %} ### Headers | Header | Value | | -------------- | ------------------ | | `Content-Type` | `application/json` | ### Request body
FieldPositionTypeRequiredDescription
addressbodystringtrueThe buyer's public address.
privateKeybodystringtrueThe buyer's private key.
estimateTrxbodynumbertrueThe amount of TRX to be paid, in SUN (the estimateTrx value from Step 1).
### Request body example ```json { "address": "TM6ZeEgpefyGWeMLuzSbfqTGkPv8Z65432", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000 } ``` ### Response ```json { "visible": false, "txID": "795f8195893e8da2ef2f70fc3a1f2720f9077244c4b7b1c50c99c72fda675a32", "raw_data_hex": "0a02b32e2208ce1cb373c238875e4098fbd9a0eb325a68080112640a2d747970652e676f6f676c65617069732e636f6d2f70726f746f636f6c2e5472616e73666572436f6e747261637412330a1541417ca6f74356a5d4454498e3f4856c945a04ab01121541055756f33f419278d9ea059bd2b21120e6add74818e0e5a40170b8a6d6a0eb32", "raw_data": { "contract": [ { "parameter": { "value": { "to_address": "41055756f33f419278d9ea059bd2b21120e6add748", "owner_address": "41417ca6f74356a5d4454498e3f4856c945a04ab01", "amount": 2700000 }, "type_url": "type.googleapis.com/protocol.TransferContract" }, "type": "TransferContract" } ], "ref_block_bytes": "b32e", "ref_block_hash": "ce1cb373c238875e", "expiration": 1746778095000, "timestamp": 1746778035000 }, "signature": [ "xxxxxxxxxxxxxxxxxxx" ] } ``` ### Errors This endpoint does not use an `apikey` header. Authentication for the overall flow is provided by the signed transaction itself in [Step 3 — Create Order](/developers/api-reference/buy-resources/signed-tx/create-order.md); this endpoint only builds and signs the transaction. As a result it returns schema-validation errors (`400`) rather than `401` when the request is malformed. **`400 Bad Request`** — a required field (`address`, `privateKey`, or `estimateTrx`) is missing or invalid. The `message` names the offending field: ```json { "statusCode": 400, "code": "FST_ERR_VALIDATION", "error": "Bad Request", "message": "body must have required property 'address'" } ``` **`404 Not Found`** — the route/path is incorrect: ```json { "message": "Route POST:/v2/... not found", "error": "Not Found", "statusCode": 404 } ``` ## Request examples {% tabs %} {% tab title="cURL" %} ```bash curl -X POST https://api.tronsave.io/v2/signed-tx \ -H "Content-Type: application/json" \ -d '{ "address": "YOUR_TRON_ADDRESS", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000 }' ``` {% endtab %} {% tab title="JavaScript" %} ```javascript const res = await fetch("https://api.tronsave.io/v2/signed-tx", { method: "POST", headers: { "Content-Type": "application/json", }, body: JSON.stringify({ address: "YOUR_TRON_ADDRESS", privateKey: "YOUR_PRIVATE_KEY", estimateTrx: 13500000, }), }); const data = await res.json(); console.log(data); ``` {% endtab %} {% tab title="Python" %} ```python import requests res = requests.post( "https://api.tronsave.io/v2/signed-tx", headers={"Content-Type": "application/json"}, json={ "address": "YOUR_TRON_ADDRESS", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000, }, ) print(res.json()) ``` {% endtab %} {% tab title="Java" %} ```java import java.net.URI; import java.net.http.HttpClient; import java.net.http.HttpRequest; import java.net.http.HttpResponse; public class GetSignedTransaction { public static void main(String[] args) throws Exception { String body = """ { "address": "YOUR_TRON_ADDRESS", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000 } """; HttpClient client = HttpClient.newHttpClient(); HttpRequest request = HttpRequest.newBuilder() .uri(URI.create("https://api.tronsave.io/v2/signed-tx")) .header("Content-Type", "application/json") .POST(HttpRequest.BodyPublishers.ofString(body)) .build(); HttpResponse response = client.send(request, HttpResponse.BodyHandlers.ofString()); System.out.println(response.body()); } } ``` {% endtab %} {% tab title="Go" %} ```go package main import ( "bytes" "fmt" "io" "net/http" ) func main() { body := []byte(`{ "address": "YOUR_TRON_ADDRESS", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000 }`) req, _ := http.NewRequest("POST", "https://api.tronsave.io/v2/signed-tx", bytes.NewBuffer(body)) req.Header.Set("Content-Type", "application/json") resp, err := http.DefaultClient.Do(req) if err != nil { panic(err) } defer resp.Body.Close() data, _ := io.ReadAll(resp.Body) fmt.Println(string(data)) } ``` {% endtab %} {% tab title="Rust" %} ```rust use serde_json::json; fn main() -> Result<(), Box> { let client = reqwest::blocking::Client::new(); let res = client .post("https://api.tronsave.io/v2/signed-tx") .header("Content-Type", "application/json") .json(&json!({ "address": "YOUR_TRON_ADDRESS", "privateKey": "YOUR_PRIVATE_KEY", "estimateTrx": 13500000 })) .send()?; println!("{}", res.text()?); Ok(()) } ``` {% endtab %} {% endtabs %} {% hint style="warning" %} This endpoint requires the buyer's `privateKey` in the request body. Only call it from a trusted server-side environment, never from client-side code. If you prefer not to send your private key, use [Option 1](#option-1-write-your-own-function) and sign the transaction locally. {% endhint %} ## Next steps * [Step 1 — Estimate TRX](/developers/api-reference/buy-resources/signed-tx/estimate-trx.md) * [Step 3 — Create Order](/developers/api-reference/buy-resources/signed-tx/create-order.md) * [Buy with Signed Transaction overview](/developers/api-reference/buy-resources/signed-tx.md)