Blackbox vs Cluely

The short answer

Choose Blackbox if you run calls where being wrong is expensive — security reviews, pricing negotiations, technical demos — and you have the documents that contain the right answers. Choose Cluely if you want a broad assistant across many meeting types and screen sharing is not part of your day.

At a glance

Cluely's plan details are taken from its published pricing and change from time to time — check cluely.com/pricing before you decide.

Where the two are genuinely alike

It is worth being clear about this, because most comparison pages are not. Blackbox and Cluely share the same core idea, and it is a good one. Both run as a desktop application that listens to the call audio on your own machine. Neither dials into the meeting, so neither shows up in the participant list as “Notetaker” or “Recording Bot”, and nobody has to approve a guest before you can use it.

Both also answer in real time rather than after the fact. That is the dividing line between this category and traditional meeting assistants: a summary emailed to you an hour later cannot help with the question you were asked thirty seconds ago. If you are comparing either of these against a conventional notetaker, that is the difference that matters most.

Difference one: what happens when you share your screen

Not joining the call keeps you out of the participant list. It does nothing about the moment you present. The instant you share your screen, anything drawn on top of it is visible to everyone watching — and on a demo or a security review, screen sharing is most of the call.

Blackbox excludes its overlay from screen capture at the operating system level, on macOS and Windows, on every plan. Your prompt sits on your display and is absent from the stream the other side receives. There is no window to remember to move and no second monitor to rely on.

Cluely offers the same capability, but its published plans put undetectability on a separate, substantially more expensive tier than its standard paid plan. If invisibility during screen sharing is the reason you are buying one of these tools at all, compare the tier that actually includes it rather than the headline price.

Difference two: where the answers come from

A general model answering “what is your data retention policy?” will produce something fluent and plausible. On a procurement call, plausible is worse than useless — it is a commitment you did not mean to make, said out loud, on the record.

Blackbox is built around a private knowledge vault. You upload the documents that contain your real answers — security whitepapers, pricing tiers, SLAs, objection battlecards, onboarding runbooks — and every answer is drawn from them. Ask it about your retention policy and it reads back what your own addendum says, not what a model imagines a SaaS company would say.

This matters most in exactly the calls where real-time help is worth paying for: the security questionnaire, the competitive displacement, the technical objection from the one engineer in the room who knows the stack. Those answers exist in your company already. The job is surfacing the right one inside a few seconds.

Speed, and why a few seconds decides it

A live assistant is only useful inside the pause where an answer is still natural. Past roughly five seconds, the silence is doing more damage than the answer repairs, and the other side has already started filling it. Blackbox targets sub-second transcription into an answer that begins appearing while the question is still landing.

When you trial either tool, time this yourself rather than trusting a marketing figure, ours included. Ask a colleague to put a hard question to you on a real call and count how long you sit there.

When Cluely is the better choice

If you want to try the category without paying, Cluely has a free tier and Blackbox does not. If your meetings are varied and unstructured, and you have no document set worth uploading, the grounding that makes Blackbox valuable has nothing to work with. And if you never share your screen, the invisibility difference that this page spends most of its length on does not apply to you.

Frequently asked questions

Is Blackbox or Cluely better for sales calls?

Blackbox, if your answers need to come from your own pricing sheets, security documentation and objection battlecards. You upload those once and every answer is drawn from them. Cluely is stronger if you want a general-purpose assistant across many kinds of meeting and do not have a document set to ground it in.

Can people on the call see Blackbox or Cluely?

Neither joins the call as a participant, so no bot appears in the attendee list on either. The difference is what happens when you share your screen: Blackbox hides its overlay from screen capture on every plan, while Cluely's published plans place undetectability on a separate, higher tier.

Do Zoom, Teams or Google Meet detect these tools?

Both read audio locally on your machine rather than joining the meeting, so neither appears as a participant or a recording bot. What a meeting platform can see is your shared screen, which is why overlay behaviour during screen sharing is the thing worth checking before you buy.

How much does Blackbox cost compared to Cluely?

Blackbox Pro is $30 a month with screen-share invisibility included. Cluely publishes a free tier and a lower-priced paid tier, with undetectability sold on a separate higher plan. Check both pricing pages before deciding, as these change.

Does Blackbox work on Windows as well as macOS?

Yes. Blackbox ships native desktop apps for both macOS and Windows, and the invisible overlay works on both.