The plus character does not have one universal meaning in every query-processing context. The form profile follows application/x-www-form-urlencoded behavior and decodes plus as a space. The component profile follows encodeURIComponent-style component handling and leaves a literal plus unchanged unless it appears as percent-2B. Write down the selected profile and compare the source, decoded rows and canonical query together. That evidence makes a later mismatch reproducible without pretending that this parser defines how every server, framework or signature system will interpret the same bytes.

Form mode maps plus to space

With source q=blue+shoes, form mode decodes the value as blue shoes and canonicalizes it back to blue+shoes. A literal plus must be encoded as percent-2B. The encoder also escapes characters excluded from the form percent-encode safe set. Keep duplicate names as separate ordered rows until the receiving application states its own policy. Converting early to a plain object can discard values, change their order or hide whether a parameter appeared without an equals sign in the original query.

Component mode preserves literal plus

With the same source, component mode produces blue+shoes because plus is ordinary data. A space is written as percent-20 in canonical output. This profile is useful when comparing separately encoded parameter components, but it does not reinterpret a complete URL. A successful decode only establishes the text produced by these explicit rules. It does not validate a destination URL, authorize a redirect, verify a signature, detect an attack or prove that another implementation applies identical limits and error handling.

Choose from the producer contract

Do not select a profile merely because one output looks familiar. Use the documented behavior of the producer and receiver, then preserve the profile with the reproduced case. If those systems disagree, the visible plus-versus-space difference is evidence to investigate, not permission to guess. QueryLens performs the transformation locally and sends no query content to a product backend. Still review copied output before reuse: encoded data can contain identifiers, search terms or other sensitive text, and the destination remains responsible for validation and access control.