strapi/strapi · warning · ParsingFileError

Wrong format uploaded (accepted formats only: jpeg, jpg, png

Error message

Wrong format uploaded (accepted formats only: jpeg, jpg, png, svg).

What it means

Thrown by parseFileMetadatas when the uploaded file's MIME type is not in ACCEPTED_FORMAT. The error wraps a MessageDescriptor so the admin UI can render a localized message; accepted formats are jpeg/jpg/png/svg per the defaultMessage.

Source

Thrown at packages/core/admin/admin/src/pages/Settings/pages/ApplicationInfo/utils/files.ts:33

interface ImageDimensions {
  height: number;
  width: number;
}

interface ImageAsset extends ImageDimensions {
  ext: string | undefined;
  size: number;
  name: string;
  url: string;
  rawFile: File;
}

const parseFileMetadatas = async (file: File): Promise<ImageAsset> => {
  const isFormatAuthorized = ACCEPTED_FORMAT.includes(file.type);

  if (!isFormatAuthorized) {
    throw new ParsingFileError('File format', FILE_FORMAT_ERROR_MESSAGE);
  }

  const fileDimensions = await new Promise<ImageDimensions>((resolve) => {
    const reader = new FileReader();
    reader.onload = () => {
      const img = new Image();
      img.onload = () => {
        resolve({ width: img.width, height: img.height });
      };
      img.src = reader.result as string;
    };
    reader.readAsDataURL(file);
  });

  const areDimensionsAuthorized =
    fileDimensions.width <= DIMENSION && fileDimensions.height <= DIMENSION;

  if (!areDimensionsAuthorized) {

View on GitHub (pinned to 4a4101264d)

Solutions

1. Convert the asset to png, jpg/jpeg, or svg before uploading.
2. If you need webp/gif support, extend ACCEPTED_FORMAT in ./constants and update the defaultMessage.
3. Verify the file's actual MIME type (file.type) in the browser devtools before upload.
4. Strip any renamed extension so the OS-reported MIME type matches the content.

Example fix

// before
const ACCEPTED_FORMAT = ['image/jpeg', 'image/png', 'image/svg+xml'];
// after
const ACCEPTED_FORMAT = ['image/jpeg', 'image/png', 'image/svg+xml', 'image/webp'];

const ACCEPTED_FORMAT = ['image/jpeg', 'image/png', 'image/svg+xml'];
if (!ACCEPTED_FORMAT.includes(file.type)) {
  // surface a friendly message to the user before upload
}

const ACCEPTED_FORMAT = ['image/jpeg', 'image/png', 'image/svg+xml'] as const;
type AcceptedMime = typeof ACCEPTED_FORMAT[number];
function isAcceptedMime(m: string): m is AcceptedMime {
  return (ACCEPTED_FORMAT as readonly string[]).includes(m);
}

When it happens

Trigger: Uploading a webp, gif, bmp, or heic file to the Application Info customization modal (logo / favicon upload).

Common situations: Designer exports a webp logo; favicon uploaded as .ico; browser reports a generic MIME type because the extension was renamed.

Related errors

• The file uploaded is too large (max dimension: {dimension}x{
• Email already taken
• A user with this email address already exists
• Name already taken
• Name already taken

AI-assisted analysis of strapi/strapi@4a4101264d (2026-08-12). Data as JSON: /api/errors/00c82a727023cbc6. Report an issue: GitHub.