Sending files

There are three ways to send files (photos, stickers, audio, media, etc.):

1. If the file is already stored somewhere on the Telegram servers, you don't need to reupload it: each file object has a file_id field, simply pass this file_id as a parameter instead of uploading. There are no limits for files sent this way.
2. Provide Telegram with an HTTP URL for the file to be sent. Telegram will download and send the file. 5 MB max size for photos and 20 MB max for other types of content.
3. Post the file using multipart/form-data in the usual way that files are uploaded via the browser. 10 MB max size for photos, 50 MB for other files.

Sending by file_id

• It is not possible to change the file type when resending by file_id. I.e. a video can't be sent as a photo, a photo can't be sent as a document, etc.
• It is not possible to resend thumbnails.
• Resending a photo by file_id will send all of its sizes.
• file_id is unique for each individual bot and can't be transferred from one bot to another.
• file_id uniquely identifies a file, but a file can have different valid file_ids even for the same bot.

Sending by URL

• When sending by URL the target file must have the correct MIME type (e.g., audio/mpeg for sendAudio, etc.).
• In sendDocument, sending by URL will currently only work for .PDF and .ZIP files.
• To use sendVoice, the file must have the type audio/ogg and be no more than 1MB in size. 1-20MB voice notes will be sent as files.
• Other configurations may work but we can't guarantee that they will.