encoding

URL Encoder / Decoder API Reference

Encode any string for safe use in a URL or query parameter using percent-encoding (RFC 3986), or decode a percent-encoded string back to plain text. Supports both full URL encoding (preserves ://?=& structure) and component encoding (encodes every special character). Shows a character-by-character encoding table for reference.

Endpoint

POST/api/url-encoder

Full URL: https://quickhelp.dev/api/url-encoder

Request

Content-Type: application/json. No authentication required for the anonymous free tier (30 req/min per IP).

Field	Type	Required	Description
input	string	Yes	The string to encode or decode
mode	default	No	encode-component — encodes every character except A–Z a–z 0–9 - _ . ! ~ * ' ( ); encode-full — preserves URL structure characters (: / ? # [ ] @ ! $ & ' ( ) * + , ; =); decode — converts %XX sequences back to plain text

Response

Returns application/json. On error, returns a JSON object with an error string field and an appropriate HTTP status code.

Field	Type	Description
output	string	The encoded or decoded result
mode	enum	—
changed	boolean	True if the output differs from the input
encoding_table	array	Characters that were changed, for reference (encode modes only)

Example

Encode a query parameter value

curl

curl -X POST https://quickhelp.dev/api/url-encoder \
  -H 'Content-Type: application/json' \
  -d '{"input":"hello world & more=stuff","mode":"encode-component"}'

Request body

{
  "input": "hello world & more=stuff",
  "mode": "encode-component"
}

Response

{
  "output": "hello%20world%20%26%20more%3Dstuff",
  "mode": "encode-component",
  "changed": true,
  "encoding_table": [
    {
      "original": " ",
      "encoded": "%20"
    },
    {
      "original": "&",
      "encoded": "%26"
    },
    {
      "original": "=",
      "encoded": "%3D"
    }
  ]
}

Error codes

Status	Meaning
200	Success — result in response body
400	Bad request — invalid input; error field describes the problem
404	Tool not found
429	Rate limit exceeded (30 req/min anonymous, 300 req/min free key)
500	Internal server error — transient; retry with exponential back-off

OpenAPI spec

The full OpenAPI 3.1 specification for all tools is available at /openapi.json. Import it into Postman, Insomnia, or any OpenAPI-compatible client to get all endpoints with schema validation automatically.