Features & Guide

Everything PhantomAI can do, explained step by step. If you can highlight text or drag a box, you already know most of it.

Getting Started

After installing PhantomAI from the Chrome Web Store, click the extension icon in your browser toolbar. You will see a sign-in screen. Click "Sign in on phantom-ai.app" to create an account or log in.

Once signed in, you will see your email, current plan, and daily query count. All features are now active on every webpage you visit. No setup or configuration needed.

If you ever get signed out, just open the extension popup and sign in again. Your settings and documents are saved to your browser and will still be there.

Text Queries

This is the simplest way to use PhantomAI. It works on any webpage.

  1. Highlight any text on the page by clicking and dragging over it, just like you would to copy something.
  2. Press the action key (default: ]). That's it.

PhantomAI sends the highlighted text to AI and shows you the answer as floating text at the bottom of your screen. The answer disappears automatically after a few seconds.

This works everywhere: Google Forms, Canvas, Blackboard, Coursera, Wikipedia, PDFs open in Chrome, and any other webpage.

Screenshot Queries

Some questions are not just text. They include images, diagrams, math equations, charts, or things you cannot highlight. Screenshot mode handles these.

Using the keyboard

  1. Hold Ctrl (or Cmd on Mac) and press the action key (default: ]).
  2. Your screen dims slightly. Click and drag a box around whatever you want AI to look at.
  3. Release the mouse. PhantomAI captures that area and sends it to AI.

Using the mouse only

  1. Triple-click on any empty space on the page (not on text).
  2. Your screen enters capture mode. Drag a box around the question or image.
  3. Release to send it.

Press Esc at any time to cancel capture mode without sending anything.

The AI reads everything inside your selection box: text, images, diagrams, handwriting, math notation, and more.

Pasting Answers

After you get an answer from any query (text or screenshot), PhantomAI remembers it. You can paste it into any text field on the page.

  1. Click into a text field where you want the answer to go (a form input, a text box, a search bar, etc.).
  2. Press the paste key (default: [).

The answer gets inserted into that field. If you have Type Mode turned on (it is on by default), the answer types out character by character instead of appearing all at once.

You can paste the same answer multiple times into different fields. It always pastes your most recent AI answer until you make a new query.

Reference Images

Sometimes you want AI to see extra information every time you ask a question. For example, a formula sheet, a reference table, or notes from a previous page. Reference images let you do this.

  1. Hold Ctrl (or Cmd) and press the context key (default: \).
  2. Drag a box around whatever you want to save as a reference.
  3. Release. The screenshot is saved.

You can save multiple reference images. From now on, every query you make (text or screenshot) will include these reference images so AI can see them alongside your question.

To clear all saved reference images, hold Ctrl + Shift and press the context key.

You can see how many reference images you have saved by opening the extension popup and looking at the Screenshots section at the bottom.

Context Documents

You can upload files that AI will use as background knowledge when answering your questions. This is useful for study guides, lecture notes, or any reference material.

How to upload

  1. Open the PhantomAI extension popup.
  2. Expand the Documents section.
  3. Drag files into the drop zone, or click it to browse your computer.

Supported file types

  • PDF - the text content is extracted automatically
  • TXT - plain text files
  • MD - Markdown files
  • CSV - spreadsheet data

Once uploaded, the AI automatically searches your documents for relevant information every time you ask a question. You do not need to do anything special. If your documents contain an answer or useful context, AI will use it.

You can remove individual documents by clicking the X next to them, or clear everything with the Clear All button.

Answer Display Settings

These settings control how AI answers look on your screen. Open the extension popup and expand the Answer Display section to find them.

Opacity

How see-through the answer text is. At 100% the text is fully solid. Lower values make it more transparent, which can be less noticeable on screen.

Text Size

The font size of the answer text in pixels. Bigger numbers mean bigger text. The default is 25px, which works well on most screens.

Color

The color of the answer text. Click the color swatch to pick any color you want. Choose something that is easy to read against the websites you use most.

Chars

The maximum number of characters shown in the floating answer text. If the AI response is longer than this, only the first part shows on screen. You can still paste the full answer with the paste key. The default is 100 characters.

X Offset / Y Offset

Moves the answer text left/right (X) or up/down (Y) from its default position at the bottom center of the screen. Useful if the default position overlaps with something on the pages you use.

Duration

How many seconds the answer stays on screen before fading away. The default is 5 seconds. Set it longer if you need more time to read answers, or shorter if you want them to disappear quickly.

Type Mode

When turned on, pasting an answer into a text field types it out one character at a time instead of inserting it all at once. This looks more natural. On by default.

Detail Overlay

When turned on, a draggable panel appears on screen with the full AI response. You can move it around and it stays until you close it. Useful for long answers that do not fit in the floating text.

Capture Pill Settings

When you enter capture mode (to take a screenshot), a small pill appears in the corner of your screen to let you know the mode is active. These settings control how that pill looks.

Ask Label

The text shown on the pill when you are capturing a question screenshot. Default is ***. You can change it to anything you want, like "ask" or "?".

Context Label

The text shown when you are capturing a reference image. Default is + ctx. Shows alongside the ask label if you already have saved reference images.

Colors

Two color pickers: one for the pill background and one for the pill text. Pick colors that are subtle enough to not draw attention but visible enough that you know capture mode is active.

Size

Makes the pill bigger or smaller. 100% is the base size. 200% doubles it. Lower values like 50% make it tiny.

Opacity

How transparent the pill is. Lower values make it harder to see, which can be useful if you want it to be very subtle.

Hotkey Settings

PhantomAI uses three keys for its main actions. You can change any of them by opening the extension popup and clicking on the key button you want to change.

Action Key ]

The main key for everything. Press it after highlighting text to get an AI answer. Hold Ctrl/Cmd and press it to enter screenshot capture mode.

Paste Key [

Press this while your cursor is in a text field to paste the last AI answer. Works with any input, textarea, or editable area on any page.

Context Key \

Hold Ctrl/Cmd and press this to capture a reference image. Hold Ctrl/Cmd + Shift and press it to clear all saved reference images.

To change a key: click the key button in the popup, then press the new key you want to use. The change saves automatically. Avoid keys that conflict with browser shortcuts.

Plans & Limits

PhantomAI offers three plans. All plans have access to every feature. The only difference is how many AI queries you can make per day.

Free

20 queries per day. Standard AI model. No credit card needed. All features included.

Pro - $8/month

200 queries per day. Smarter AI model that gives more accurate and detailed answers. Priority support.

Unlimited - $20/month

No daily query limit. Most powerful AI model available for the best possible answers. Everything in Pro.

Query counts reset every day at midnight UTC (7:00 PM Eastern / 4:00 PM Pacific). You can see your current count in the extension popup.

You can upgrade, downgrade, or cancel your plan at any time from the Account page or through the extension popup.