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415

HTTP 415 Unsupported Media Type: the request content format is not supported

Verified with sources2 sourcesReviewed Aug 22, 2026
Technician coming? See what they must show you

Risk level

Low

Usually safe to check without specialist tools.

Urgency

Medium

Quick answer

HTTP 415 means the origin refuses the request because its content format is not supported for that method and target resource.

Safety first

Stop and check this first

  • Never relabel arbitrary bytes as an accepted media type. Validate and serialize the content according to the endpoint contract.

Safe checks you can perform

  • Compare Content-Type with the documented method
  • Inspect the serialized bytes safely
  • Send one minimal valid example

Leave these tasks to a qualified professional

  • Do not attempt this professional task: Trace media-type selection and decoding

What a technician must be able to justify

Technician visit

These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.

These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.

  1. Trace media-type selection and decoding

    What they doInspect gateway transformations, framework parsers and endpoint consumes declarations to find the first unsupported representation.

Before accepting a part or repair

Nothing has been shown yet. Do not accept a part swap based on the code alone.

Follow these steps

Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.

  1. Compare Content-Type with the documented method

    Tools required

    Verify the exact media type, parameters and multipart boundary required for this route and HTTP method.

    Never relabel arbitrary bytes as an accepted media type. Validate and serialize the content according to the endpoint contract.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

  2. Inspect the serialized bytes safely

    Tools required

    Confirm that the body encoding matches its header after redacting credentials and personal payload fields.

    Never relabel arbitrary bytes as an accepted media type. Validate and serialize the content according to the endpoint contract.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

  3. Send one minimal valid example

    No special tools

    Use the service's smallest documented request to separate format handling from business validation such as 422.

    Never relabel arbitrary bytes as an accepted media type. Validate and serialize the content according to the endpoint contract.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

Still not solved

If the error persists, stop here. See what the technician must do and show you.

Where this code applies

A code is meaningful only inside the right product and version context.

Primary scope

System
Software and digital services
Brand
HTTP
Product type
HTTP service

Known code variants

  • 415 Nicht unterstützter Medientyp
  • 415 Tipo de medio no compatible
  • 415 Tipo di contenuto non supportato
  • 415 Type de média non pris en charge
  • 415 Unsupported Media Type
  • código HTTP 415
  • error HTTP 415
  • événement Fronius 415
  • evento Fronius 415
  • Fronius Ereignis 415
  • Fronius event 415
  • Fronius inverter 415
  • Fronius Symo / Eco 415
  • Fronius Wechselrichter 415
  • HTTP 415
  • HTTP error 415
  • HTTP status 415
  • inversor Fronius 415
  • inverter Fronius 415
  • onduleur Fronius 415
  • status code 415

What it means

The mismatch can come from Content-Type, Content-Encoding or inspection of the data itself. It is about request content format, not the preferred response format.

Warnings and stop conditions

  • Higheditorial warning

    Never relabel arbitrary bytes as an accepted media type. Validate and serialize the content according to the endpoint contract.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

Symptoms and causes

Probable causes · in order

  • Content-Type does not match the endpoint contractConfirmed

    The request can declare JSON, form data or another type that the target method does not consume.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

  • The declared format and actual bytes disagreePossible

    A wrong boundary, charset, content encoding or serialized body can fail even when the media-type label looks correct.

    Evidence: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registry

Virtual technician

Does 415 still appear after these checks?

Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.

Start diagnosis

Sources and technical references

  1. 1

    RFC 9110 section 15.5.16 - 415 Unsupported Media Type

    Internet Engineering Task Force · 2022 · official_doc

  2. 2

    IANA Hypertext Transfer Protocol Status Code Registry

    Internet Assigned Numbers Authority · 2025 · official_doc

Sources: RFC 9110 section 15.5.16 - 415 Unsupported Media Type · IANA Hypertext Transfer Protocol Status Code Registryreviewed 2026-08-22 · verified

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