Not every question is text. You can attach images and PDFs to a message, or dictate it out loud instead of typing. This is one of the features of Secret Chat AI, the AI aggregator.
Attaching images
Drag a picture onto the chat, or use the attach button. JPEG, PNG, GIF and WebP are accepted, up to 25 MB each. Models that can see will read a screenshot, a photograph of a document, a chart, a diagram or a design and answer questions about it — and in the Image Generator an attached picture becomes the starting point for an edit rather than a question.
Attaching PDFs
PDFs go the same way. The size limit varies by model and is shown in the attach button's tooltip for whichever model you have selected. Useful for the things that are painful to paste: a contract you want summarised clause by clause, a paper you want the method of explained, a manual you want one specific answer out of.
Which models can read what
Capabilities differ by provider, and the app follows the selected model rather than pretending otherwise — the attach button simply stops offering file types the current model cannot read.
- ChatGPT, Claude, Gemini, Grok and Perplexity read both images and PDFs.
- DeepSeek USA is text-only. No provider endpoint on its allowlist accepts an image, so there is no attach button on it at all. Switch models for anything with a file in it.
If you attach a file and then switch to a model that cannot read it, the app tells you rather than quietly sending a question with the attachment missing.
Voice input
Press the microphone and speak; recording shows a timer, and when you stop, the audio is transcribed and the text is dropped into the message box. You can then edit it before sending — it fills in the input, it does not send on your behalf. Convenient for long messages, awkward spelling, and anything you would rather say than type.
Two things to know: voice transcription is a paid feature, not part of the free daily quota, and it needs a browser with microphone recording support — the button tells you if yours cannot do it.
What leaves your device
Attachments are stored in your own browser (OPFS) along with the rest of your history, and they are included when you export your data. But to be answered about, a file has to be read by the model, so its contents do go to the provider with your message — anonymously, under our gateway's credentials rather than your identity, but in full. Voice is the same: the recording is transcribed by a provider before it becomes text.
This is where the standing limit bites hardest, because files carry far more than you consciously put in a sentence. A photographed letter has a letterhead and an address on it. A PDF contract has the parties' names throughout. A scanned report may have a patient identifier in the header you were not even looking at. Secret Chat AI removes you from your queries — it does not remove the data from your messages, and it cannot redact a document for you. Check what is actually on the page before you attach it, and crop or redact when it does not need to be there.