URL Encoder/Decoder
Encode and decode URLs and query strings
Use URL Encoder/Decoder
Active sample: Search parameter. Convert it, then reuse the output to check whether a second pass would cause double encoding.
Quick Reference:
Output details
Copy-ready workflow handoff
Encode or decode URL components before copying API queries, redirect URLs, or support links.
Do not decode the same value twice if it intentionally contains encoded delimiters.
URLs can contain emails, tokens, campaign IDs, account IDs, and signed state values.
Copy this after replacing the bracketed output with the live result from the tool.
URL encoding handoff: [paste the current tool output here]. Workflow: Encode or decode URL components before copying API queries, redirect URLs, or support links. Sample to test: Review one redirect parameter, search query, callback URL, or signed URL component. Output to review: Copy the encoded or decoded URL component with reserved characters checked. Invalid/error check: Do not decode the same value twice if it intentionally contains encoded delimiters. Privacy note: URLs can contain emails, tokens, campaign IDs, account IDs, and signed state values. Next check: Use URL Query Builder when multiple parameters must be assembled together.
Assumptions
Use URL Encoder/Decoder for encoding and auth debugging work when you need a local browser check and output you can review before using it in the next step.
Worked example
When To Use URL Encoder/Decoder
- Paste a real example into URL Encoder/Decoder that includes the edge case you need to check.
- Review whether the output matches inspect transformed strings before they move into requests or templates before using it in the next step.
Sample Input And Output Checks
- Start with a sample that includes the failure you are trying to reproduce, not only a clean placeholder.
- Review padding, escaping boundaries, token segments, and copied delimiters before trusting the output.
- Treat decoded or escaped output as readable input for the next step, not as automatically trusted data.
About This Tool
URL encoding, also known as percent-encoding, is a mechanism for encoding information in a URI (Uniform Resource Identifier). It replaces unsafe ASCII characters with a "%" followed by two hexadecimal digits representing the character's ASCII code.
Why URL Encoding is Necessary
URLs can only contain a limited set of characters from the ASCII character set. Special characters, spaces, and non-ASCII characters must be encoded to be safely transmitted in URLs. URL encoding ensures that data is properly formatted and won't break the URL structure or cause security issues.
Common Use Cases
For encoding QR codes with URL parameters, use our QR Code Generator tool.
- Query Parameters: Encoding search terms and form data in URLs
- API Requests: Safely passing parameters to REST APIs
- Special Characters: Handling spaces, &, =, ?, and other reserved characters
- International Text: Encoding non-ASCII characters like Chinese, Arabic, or emoji
- Data Transmission: Safely transmitting user input through URLs
Component vs Full URL Encoding
encodeURIComponent encodes all special characters except: A-Z a-z 0-9 - _ . ! ~ * ' ( ). Use this for encoding individual URL parameters or query string values. encodeURI preserves URL structure characters like :, /, ?, and & while encoding other special characters. Use this for encoding complete URLs while maintaining their structure.
Reserved Characters
Reserved characters in URLs include: ! * ' ( ) ; : @ & = + $ , / ? # [ ]. These characters have special meaning in URLs and must be encoded when used as data. For converting URLs to JSON format, use our JSON Formatter tool.
encodeURI vs encodeURIComponent
Many encoding bugs happen because developers use the right function in the wrong place. encodeURI() is intended for a complete URL and preserves separators such as :, /, ?, and &. encodeURIComponent() is meant for one parameter value and escapes those separators as data. If a redirect URL breaks only after a query string is appended, the likely issue is that a full URL was encoded as a component or a component was inserted into a URL without encoding at all. This page helps you test both cases quickly before you update application code.
High-Value URL Encoding Use Cases
Practical searches around this topic usually come from API debugging, analytics tags, OAuth redirects, form submission links, QR code payloads, and multilingual search parameters. Teams often use a URL encoder to safely pass email addresses, callback URLs, search terms, nested JSON fragments, or user-entered text through a query string without breaking routing. After you finish encoding a shareable link, our QR Code Generator is a useful next step for packaging the final URL.
Double-Encoding and Plus Sign Pitfalls
If a URL looks correct but the server receives garbled characters, look for double-encoding first. A value like %2520 usually means an existing percent-encoded string was encoded again. Also remember that some systems treat + as a space in query strings, while others expect a literal plus sign to be encoded as %2B. When debugging a failing request, compare the raw source value, the encoded value, and the decoded server-side value side by side so you can see exactly where the transformation went wrong.
When Encoding Produces No Change
A no-change output usually means the string contains only URL-safe characters for the selected mode. That is not automatically a failure. Check whether you selected full URL mode for a complete link or component mode for a single parameter value, then test one realistic value that includes spaces, ampersands, equals signs, or non-ASCII text. If the URL contains a JWT or Base64 payload, inspect that inner value with the JWT Decoder or Base64 Encoder/Decoder before blaming percent encoding.
Sample And Checks
Sample input for component mode: https://app.example.com/[email protected]&next=/billing?tab=invoices
Expected output: https%3A%2F%2Fapp.example.com%2Freturn%3Femail%3Davery%40example.com%26next%3D%2Fbilling%3Ftab%3Dinvoices
- Common errors: encoding a full URL as a component when only one query value should be escaped, decoding twice, and confusing plus signs with spaces.
- Next checks: break the final link down with URL Parameter Extractor, rebuild query strings with URL Query Builder, inspect token values with the JWT Decoder, and decode embedded Base64 with the Base64 Encoder/Decoder.
Privacy note: Encoding runs locally, but URLs often expose emails, callback codes, signed state, and campaign IDs. Redact those values before sharing an encoded link.