> For the complete documentation index, see [llms.txt](https://docs.fonbnk.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fonbnk.com/v1.5/endpoints/util.md).

# Util

Utility

## Check address

> Check if the provided wallet address was used in the Fonbnk system

```json
{"openapi":"3.1.0","info":{"title":"Fonbnk On-ramp API","version":"1.0.0"},"tags":[{"name":"util","description":"Utility"}],"servers":[{"url":"https://sandbox-api.fonbnk.com","description":"Development server"},{"url":"https://api.fonbnk.com","description":"Production server"}],"security":[{"ClientIdHeader":[]},{"TimestampHeader":[]},{"SignatureHeader":[]}],"components":{"securitySchemes":{"ClientIdHeader":{"type":"apiKey","in":"header","name":"x-client-id","description":"Your client ID"},"TimestampHeader":{"type":"apiKey","in":"header","name":"x-timestamp","description":"The Unix timestamp of the request signature"},"SignatureHeader":{"type":"apiKey","in":"header","name":"x-signature","description":"HMAC-SHA256 signature generated using your secret"}}},"paths":{"/api/util/check-address":{"post":{"tags":["util"],"summary":"Check address","description":"Check if the provided wallet address was used in the Fonbnk system","operationId":"checkAddress","requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","required":["address"],"properties":{"address":{"type":"string"}}}}}},"responses":{"200":{"description":"Address usage status","content":{"application/json":{"schema":{"type":"object","properties":{"used":{"type":"boolean"}}}}}}}}}}}
```

## Get supported countries with KYC rules

> Returns a list of supported countries with KYC rules depends on order amount

```json
{"openapi":"3.1.0","info":{"title":"Fonbnk On-ramp API","version":"1.0.0"},"tags":[{"name":"util","description":"Utility"}],"servers":[{"url":"https://sandbox-api.fonbnk.com","description":"Development server"},{"url":"https://api.fonbnk.com","description":"Production server"}],"security":[{"ClientIdHeader":[]},{"TimestampHeader":[]},{"SignatureHeader":[]}],"components":{"securitySchemes":{"ClientIdHeader":{"type":"apiKey","in":"header","name":"x-client-id","description":"Your client ID"},"TimestampHeader":{"type":"apiKey","in":"header","name":"x-timestamp","description":"The Unix timestamp of the request signature"},"SignatureHeader":{"type":"apiKey","in":"header","name":"x-signature","description":"HMAC-SHA256 signature generated using your secret"}},"schemas":{"KycDocument":{"type":"object","properties":{"_id":{"type":"string"},"type":{"type":"string","enum":["basic","advanced"]},"title":{"type":"string"},"value":{"type":"string"},"requiredFields":{"type":"object","additionalProperties":{"$ref":"#/components/schemas/KycRequiredField"}}}},"KycRequiredField":{"type":"object","properties":{"type":{"$ref":"#/components/schemas/KycRequiredFieldType"},"label":{"type":"string"},"required":{"type":"boolean"},"format":{"type":"string"},"regexp":{"type":"string"},"regexpFlags":{"type":"string"}}},"KycRequiredFieldType":{"type":"string","enum":["number","string","date","boolean","email","phone","smile-identity-images"]},"KycType":{"type":"string","enum":["basic","advanced"]}}},"paths":{"/api/util/countries":{"get":{"tags":["util"],"summary":"Get supported countries with KYC rules","description":"Returns a list of supported countries with KYC rules depends on order amount","operationId":"countries","responses":{"200":{"description":"Successful response","content":{"application/json":{"schema":{"type":"array","items":{"type":"object","properties":{"countryIsoCode":{"type":"string","description":"ISO code of the country, e.g. NG for Nigeria, KE for Kenya"},"currencyIsoCode":{"type":"string","description":"ISO code of the local currency, e.g. NGN for Nigerian Naira, KES for Kenyan Shilling"},"name":{"type":"string","description":"Name of the country, e.g. Nigeria, Kenya"},"basicDocuments":{"type":"array","description":"List of documents required for basic KYC","items":{"$ref":"#/components/schemas/KycDocument","description":"Name of the document, e.g. \"National ID\", \"Passport\""}},"advancedDocuments":{"type":"array","description":"List of documents required for advanced KYC","items":{"$ref":"#/components/schemas/KycDocument","description":"Name of the document, e.g. \"National ID\", \"Passport\""}},"kycRules":{"type":"object","properties":{"onramp":{"type":"array","items":{"type":"object","properties":{"min":{"type":"number","description":"Minimum amount in USD for KYC"},"max":{"type":"number","description":"Maximum amount in USD for KYC (exclusive)"},"type":{"$ref":"#/components/schemas/KycType"}}}},"offramp":{"type":"array","items":{"type":"object","properties":{"min":{"type":"number","description":"Minimum amount in USD for KYC"},"max":{"type":"number","description":"Maximum amount in USD for KYC (exclusive)"},"type":{"$ref":"#/components/schemas/KycType"}}}}}}}}}}}}}}}}}
```

## Get supported carriers

> Returns a list of supported carriers

```json
{"openapi":"3.1.0","info":{"title":"Fonbnk On-ramp API","version":"1.0.0"},"tags":[{"name":"util","description":"Utility"}],"servers":[{"url":"https://sandbox-api.fonbnk.com","description":"Development server"},{"url":"https://api.fonbnk.com","description":"Production server"}],"security":[{"ClientIdHeader":[]},{"TimestampHeader":[]},{"SignatureHeader":[]}],"components":{"securitySchemes":{"ClientIdHeader":{"type":"apiKey","in":"header","name":"x-client-id","description":"Your client ID"},"TimestampHeader":{"type":"apiKey","in":"header","name":"x-timestamp","description":"The Unix timestamp of the request signature"},"SignatureHeader":{"type":"apiKey","in":"header","name":"x-signature","description":"HMAC-SHA256 signature generated using your secret"}}},"paths":{"/api/util/carriers":{"get":{"tags":["util"],"summary":"Get supported carriers","description":"Returns a list of supported carriers","operationId":"carriers","responses":{"200":{"description":"Successful response","content":{"application/json":{"schema":{"type":"array","items":{"type":"object","properties":{"countryIsoCode":{"type":"string","description":"ISO code of the country, e.g. NG for Nigeria, KE for Kenya"},"carriers":{"type":"array","description":"List of carriers available for the payment channel","items":{"type":"object","properties":{"name":{"type":"string","description":"Name of the carrier, e.g. Safaricom, MTN"},"code":{"type":"string","description":"Code of the carrier, e.g. ng_mtn, ke_safaricom"}}}}}}}}}}}}}}}
```

## Get supported blockchain assets

> Returns a list of supported blockchain assets for the off-ramp and on-ramp

```json
{"openapi":"3.1.0","info":{"title":"Fonbnk On-ramp API","version":"1.0.0"},"tags":[{"name":"util","description":"Utility"}],"servers":[{"url":"https://sandbox-api.fonbnk.com","description":"Development server"},{"url":"https://api.fonbnk.com","description":"Production server"}],"security":[{"ClientIdHeader":[]},{"TimestampHeader":[]},{"SignatureHeader":[]}],"components":{"securitySchemes":{"ClientIdHeader":{"type":"apiKey","in":"header","name":"x-client-id","description":"Your client ID"},"TimestampHeader":{"type":"apiKey","in":"header","name":"x-timestamp","description":"The Unix timestamp of the request signature"},"SignatureHeader":{"type":"apiKey","in":"header","name":"x-signature","description":"HMAC-SHA256 signature generated using your secret"}},"schemas":{"OnRampNetwork":{"type":"string","enum":["POLYGON","ETHEREUM","STELLAR","AVALANCHE","SOLANA","CELO","BASE","TON","TRON","LISK","ARBITRUM","OPTIMISM","BNB"]},"OnRampAsset":{"type":"string","enum":["USDC","USDT","CUSD","CKES","CGHS","USDE"]}}},"paths":{"/api/util/assets":{"get":{"tags":["util"],"summary":"Get supported blockchain assets","description":"Returns a list of supported blockchain assets for the off-ramp and on-ramp","operationId":"blockchainAssets","responses":{"200":{"description":"Successful response","content":{"application/json":{"schema":{"type":"array","items":{"type":"object","properties":{"network":{"$ref":"#/components/schemas/OnRampNetwork"},"asset":{"$ref":"#/components/schemas/OnRampAsset"},"canOnramp":{"type":"boolean"},"canOfframp":{"type":"boolean"}}}}}}}}}}}}
```


---

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