Gemini Gems: What They Are, What They Can Do, and Where They Stop

Google publishes four separate help pages about Gemini Gems. Between them they state the minimum age, the fact that Gems exist, and almost nothing else. There is no file limit on any of them, no cap on how many Gems you can build, and no list of what a Gem can actually do. Two of the four pages answer the question by linking to a fifth page.

That gap is worth closing, because Gems are useful and they are free on every Gemini plan. This guide closes that gap. What a Gem is, the capabilities Google leaves undocumented, the real file limits, what happens to your instructions the moment you share one, and the point where Gems stop being the right tool.

The Key Takeaways

• Free on every plan: Gems cost nothing on any Gemini tier. What your plan changes is what you can feed them, not whether you get them.
• The web app, not the mobile app: Google's wording is "You can only create, edit, or delete custom Gems in the Gemini web app." That rules out the Gemini app on your phone, not your phone itself, since gemini.google.com in a mobile browser still counts.
• Sharing exposes your prompt: Google's sharing page states that any Gem instructions and files you have uploaded can be viewed by any user with access. Share the Gem, share the work.
• Ten files, 100 MB each: the real ceiling, taken from the upload page Google's Gems documentation defers to.
• One hard wall: "For now, Gems can't be used with Gemini Live." No workaround exists.

What Are Gemini Gems?

Gems are saved, reusable versions of Gemini. You write instructions once, a role, a task, a format, attach any reference files, and every new chat with that Gem starts with all of it already loaded. Google's own definition calls them "customized versions of Gemini that help you tackle repetitive tasks or get deep expertise in new areas". They are Google's answer to ChatGPT's custom GPTs, and they are free on every Gemini plan.

The comparison to OpenAI's product is the one every guide reaches for, and it holds. If you have built a custom GPT, or used ChatGPT Projects to keep related chats together, the mental model transfers directly. A Gem is a container for a system prompt plus optional reference material, given a name so you can pick it from a list instead of retyping the setup.

The Premade Gems

You do not have to build anything to start. The premade Gems Google has named include Brainstormer, Career guide, Coding partner, Learning coach and Writing editor. Google says "include" rather than giving a fixed list, and the current help centre deliberately does not enumerate them at all, so treat any article promising you exactly five as out of date. Experimental Gems and a separate Labs shelf now sit alongside them.

Two caveats that Google buries. Some premade Gems refuse to copy at all: if the "Make a copy" option is missing, that Gem is locked. And the Learning coach carries a specific hole, since Google notes it "doesn't currently support language learning", which is exactly what a lot of people try it for first.

Who Can Use Gems

You need to be 13 or older, or whatever the applicable age is in your country, with a personal Google account. Beyond that there is no gate. Gems were a Gemini Advanced perk when they launched in August 2024, which is why some older articles still describe a paywall, but Google made them free for everyone on 13 March 2025. If you are working out which Gemini tier is worth paying for, the difference is elsewhere, and our breakdown of what each Gemini plan actually costs covers where the money goes.

What Gemini Gems Can Actually Do

A Gem bundles three things. Two of them Google documents. The third it does not mention anywhere in its help centre, which is odd, because it is the one that changes how a Gem behaves most.

Saved Instructions

This is the core of it. Google recommends structuring instructions around four elements: Persona (what role to play), Task (what to do or create), Context (as much background as possible) and Format (the structure you want back). Google is explicit that you do not need all four, though using several strengthens the result.

There is a magic wand icon in the editor that hands your rough instructions to Gemini and gets back a tidier version. It is a reasonable way to learn what good instructions look like without reading a prompt engineering guide first. If you want the underlying idea rather than the Google-specific version of it, we cover how system instructions work across every major AI tool separately.

One trap worth knowing before you lose an hour: the preview panel does not save anything. You can build a Gem, test it in the preview, close the tab, and find nothing there. Click Save.

Knowledge Files

You can attach reference files that the Gem consults on every response. These can come from your device, from Google Drive, or from a Gemini Notebook. Drive files are the useful option, because the Gem reads the current version rather than a snapshot, so updating the document updates the Gem.

There is a toggle in the editor called Disable knowledge citations, which stops the Gem from footnoting your own uploaded files back at you. Leave it on while you are testing whether the Gem is really reading the files. Turn it off once you trust it and want clean output.

The Default Tool Google Never Mentions

The Gem editor has a Default tool dropdown that decides which Gemini surface every new chat with that Gem opens in. The options reported by people who have used it include no default tool, Create image, Canvas, Deep Research, Create music and Guided Learning.

This is the setting that turns a Gem from a saved prompt into something closer to a purpose-built app. A research Gem set to Deep Research opens straight into a planned, cited report. A drafting Gem set to Canvas opens the editing surface instead of a chat box. Leave it on no default tool for anything general purpose, where you want Gemini to pick.

Worth stating plainly: Google documents none of this. The phrase "default tool" appears on no Gems help page, on no product page, and nowhere in the Gemini release notes. Every description in circulation traces back to third-party write-ups, several of which share near-identical phrasing, so treat the option list above as reported rather than confirmed, and check your own editor. It may well have gained or lost an entry since anyone last wrote it down.

The Limits Google Does Not Publish

Google's Gems pages point at a separate upload article for "supported file types and limits" rather than answering. Here is what that upload article actually says, alongside the limits that have no published source at all.

The plan-dependent rows are the ones people get wrong. Upgrading to Google AI Pro or Ultra does not buy you Gems, or more Gems, or better Gems. It buys you longer video and audio uploads to feed them. Everything structural is the same on the free tier, which is unusual enough to be worth saying out loud. Our guide to what the free Gemini tier includes covers where the genuine paywalls sit.

How to Create a Gem

All of this happens in the Gemini web app at gemini.google.com. The Gemini app on your phone cannot do it, but a mobile browser pointed at the same address can, which is the distinction almost every guide collapses.

1. Open the sidebar and click Gems, then New Gem.
2. Give it a name you will recognise in a list six weeks from now.
3. Write the instructions, covering persona, task, context and format.
4. Attach knowledge files from your device, Google Drive or a Gemini Notebook.
5. Set the default tool, or leave it on no default tool.
6. Test it in the preview panel on the right.
7. Click Save. The preview does not save on its own.

Google confirms the Gem then appears in the Gemini mobile app and in the Gemini side panel in Google Workspace, ready to chat with, even though the app itself could not have built it.

Four Gem Instructions You Can Copy

Each of these follows Google's four-part structure. Paste one in, change the specifics, save.

The Editor That Does Not Rewrite

Persona: you are a line editor, not a ghostwriter. Task: mark up my draft for grammar, clarity and structure. Context: I write for a general audience and I want to sound like myself. Format: quote the original line, then the suggested change, then one sentence on why. Never return a rewritten draft.

The last sentence is the one that matters. Without it, every writing assistant hands back a version of your text with the personality sanded off.

The Meeting Note Processor

Persona: you are a chief of staff. Task: turn my raw meeting notes into decisions, owners and open questions. Context: attach your team roster and a project brief as knowledge files. Format: three headed lists, decisions first, and mark anything ambiguous as an open question rather than guessing an owner.

The Study Partner

Persona: you are a tutor who explains by asking. Task: help me understand the attached material. Context: attach your course readings. Format: never give the answer first, ask me a question that gets me to it, and only explain directly if I ask twice. Set the default tool to Guided Learning.

This one overlaps with what Google now offers natively, and if study is your main use case, Gemini's study notebooks are purpose-built for it in a way a Gem is not.

The Research Brief

Persona: you are a research analyst. Task: brief me on the topic I name. Context: I need to act on this, not admire it. Format: what is settled, what is contested, and what nobody has data on, in that order, with sources for every claim in the first two. Set the default tool to Deep Research.

How to Share a Gem

Sharing arrived on 18 September 2025, which is recent enough that plenty of guides still say Gems are private by design. They are not, and the way sharing works has a consequence most write-ups miss entirely.

How Sharing Works

Open Gems in the sidebar on the web, click Share next to your Gem, then either enter email addresses or copy a link. Google's own framing is that sharing Gems works just like sharing files in Google Drive, and the permissions match: Viewer can use the Gem, Editor can change it, share it onward, or delete it outright. You can set an expiration date and attach a message.

Give edit access carefully. Google states that any user with edit access can update or delete the Gem, and that includes the one you spent an afternoon tuning.

What the Other Person Can See

Here is the sentence that should decide whether you share anything: according to Google's documentation on sharing a Gem, any Gem instructions and files that you have uploaded to the Gem can be viewed by any user with access.

Not just used. Viewed. Your instructions are the product, and sharing the Gem hands them over in full, along with every file you attached. If you have written a Gem that encodes how your team actually operates, or attached a client document as context, sharing the Gem shares that too. There is no view-only-the-output mode.

This is also worth thinking about from the other direction. A Gem someone sends you carries instructions written by someone else, and those instructions shape every answer you get back. That is the same shape of problem we covered in how prompt injection actually works. Read a shared Gem's instructions before you trust its output.

The Notebook Catch

One restriction that will catch anyone using Google's research tools together: NotebookLM notebooks cannot be used as a source for shared Gems. A Gem you intend to share can take device files and Drive files only. Build it on a notebook and sharing breaks. Since Google now has several products with notebook in the name, our explainer on what happened when NotebookLM became Gemini Notebook is worth a read before you wire them together.

On a Workspace account, your administrator may have switched all of this off. Administrators have a single toggle, "Allow users to share Gems", that controls both sharing Gems and using ones shared with you.

Gemini Gems vs Custom GPTs

The products are close enough that the differences are what matter.

The top two rows are the surprise, and they are recent. OpenAI's current documentation states that new GPT creation and publishing are not available on personal ChatGPT accounts, naming Free, Go, Plus and Pro. Building one now requires a Business, Enterprise or Edu workspace. Existing GPTs still work and their owners can still edit them, but the door to making a new one has closed on individuals, at any price. Gems went the opposite way, from paywalled to free. Anyone comparing the two on a personal account is no longer really comparing two options.

The instructions row is the other honest split. Google spells out that a Gem behaves like a Drive file, so access means access to the contents. OpenAI simply does not address the question in its current GPT documentation, which is not the same as a guarantee of privacy. Assume a prompt you hand to someone else is a prompt you have given away, and treat Google's bluntness as the useful thing it is. If you are weighing the two assistants more broadly, our full ChatGPT versus Gemini comparison goes further than this table does.

What Most Guides Get Wrong About Gemini Gems

Three errors turn up constantly, and all three come from the same cause: the most-cited source on Gems is a Google Workspace blog post from November 2024, and the product has moved twice since.

That Gems need a subscription. The 2024 post describes custom Gems as a Gemini Advanced feature. Google made them free for everyone on 13 March 2025, and its own plan comparison now shows Gems ticked in the column for users with no Google AI plan at all.

That building a Gem needs a computer. The restriction Google states is about the Gemini mobile app, which cannot create, edit or delete Gems. The web app can, and gemini.google.com loads in a phone browser, where Google documents the taps for managing Gems. A laptop is convenient here, not required.

That Gems are private. Written before sharing existed in September 2025, and rarely updated since. Sharing exists, and it shows your instructions to everyone you share with.

Where Gems Stop Helping

Gems solve repetition. They do not solve much else, and there are three walls worth knowing about before you build your workflow around them.

The first is Gemini Live. Google's help page is unambiguous: for now, Gems cannot be used with it. If your use case is talking to an assistant hands-free, a Gem is not part of that, no matter how well tuned it is.

The second is the web app ceiling. The Gemini app on your phone can chat with a Gem and can do nothing else to it. Fixing one line of instructions means leaving the app for a browser, which is a small tax you pay every time a Gem is subtly wrong.

The third is the one that outlasts the other two. A Gem is a Gemini object. You cannot point it at Claude when Claude writes better, or at GPT when GPT reasons better. The instructions you tuned, the files you attached, the structure you worked out, all of it lives inside one vendor's product and leaves with that vendor. That is the argument for running your saved instructions in a multi-model Mac app instead, where you point the same setup at whichever model handles the task best. Our current ranking of the best AI models shows how much that choice actually moves the result.

Should You Use Gemini Gems?

If you already use Gemini and you type the same setup more than twice a week, build a Gem this afternoon. It is free, it takes ten minutes, and the premade Writing editor or Coding partner will tell you within a day whether the pattern suits how you work.

Be deliberate about two things. Do not put anything in a Gem you would not want read, because sharing it hands over the instructions in full. And do not build a large system of interlocking Gems as your only setup, because all of it is locked to one vendor and none of it exports. Build the small, repetitive ones, keep the valuable thinking somewhere you own, and treat the free tier as the whole product, because on Gems, it is.

Frequently Asked Questions