Last Updated: 13 August 2025
Why Do I Need My Own Special Key? 🔑
Think of an API key as a secure, personal key card that gives you access to Google's amazing AI service. ClarkMark AI is the special tool that lets you use this powerful technology, and your key creates a direct and private link between you and the AI.
This has two main benefits:
- It's Free: Your key unlocks the very generous free service that Google provides for you to use.
- It's Secure: It proves to Google that it's you, ensuring your work and your students' work remains completely private.
We never see or save your key; it stays safely on your computer. You can get your own free API key from Google AI Studio in just a few minutes using the link on our login page.
What are "AI Tokens"?
Imagine you're building something with Lego bricks. The AI uses special digital bricks called tokens to read your questions and write its feedback.
A short word like "the" might be one token-brick, while a longer word like "amazing" might be two. It's simple:
More words = More tokens.
A long essay or very detailed feedback just means the AI needs to use more of its token-bricks to do the job!
What Does Marking My Work "Cost"?
When we say "cost," we just mean how many tokens are used from your free plan. The total number of tokens comes from three things:
- Your Instructions: The marking rules and rubric you give the AI.
- The Student's Work: The essay or answers you want marked.
- The AI's Feedback: The helpful comments and mark it generates for you.
Here's a simple example:
- Marking one big essay of 1,500 words uses about 3,000 tokens. This includes everything from your instructions to the final feedback.
The Amazing Google Free Plan! 🎉
Google's free plan is fantastic, but it works like a ticket system at a theme park, not a giant bucket of tokens.
- You get 50 free tickets every day. Marking one student's assignment uses one ticket.
- There's also a speed rule: the system can only handle about two requests every minute.
This means you can easily mark work for your students throughout the day completely for free. You just need to give the system a little breather between requests so it doesn't get jammed up!
How Many Tokens Do You Get?
It's less about a total number of tokens and more about how many times you can "ask" the AI for help.
- It's About "Asks" Per Day Imagine you have two helpers, a super-smart one called Pro and a super-fast one called Flash.
- With Pro, you can ask for help 50 times a day. You can only ask twice every minute.
- With Flash, you can ask for help 1,500 times a day. You can ask 15 times every minute.
- Pro vs. Flash
- Pro is like the cleverest professor. It's really good at tricky tasks but takes a bit more time.
- Flash is like a super-speedy assistant. It's great for getting lots of jobs done very quickly.
- Asking for a Big Favour You could ask your helper to mark 32 pieces of homework in just one go (that's one "ask"). But, if it's a really huge job, it might take a long time and the helper could get distracted (this is called a "time out"). ClarkMark AI is smart enough to know this and provides the functionality to break the big job into smaller, staggered chunks if needed, through allowing the user to specify which students and which questions they want marking during the setup process.
- How Much Can You Ask at Once? In every single "ask," you can give the helper a massive amount of information. The limit is 1 million tokens. That's about the same as 750,000 words! So, sending 32 student assignments all at once should be absolutely fine, as long as they don't add up to more than that huge number. Remember though, those 1 million tokens are made up of the input (the data in the marking spreadsheet) and the output (the feedback provided) so the more you ask it to do, the more tokens are being used.
- A Hidden Daily Limit Sometimes, even if you haven't used up all your 50 "asks" with the Pro helper, Google might ask it to take a break if it has already processed about 6 million tokens in a day. This is a rule set by Google for their AI, and it's something ClarkMark AI can't control.
Ready for More Power? How to Upgrade
So, you want to unlock the super-speed and unlimited markings of the Pay-As-You-Go plan? Great! It's like upgrading your free theme park ticket to a VIP All-Access Pass. This is perfect for when you have a big pile of marking to get through.
So, What Does it Actually Cost? 💰
This is the best part – it's incredibly cheap. There's no monthly fee; you only pay for the extra markings you use after your 50 free ones are gone each day.
Here's how little it costs:
- Marking one large essay costs less than a single penny (or a single US cent).
- For the price of a large chocolate bar (about £1 or $1.25), you could mark over 300 essays.
- For the price of a coffee and a cake (about £5 or $6.25), you could mark over 1,500 essays!
How to Flip the Switch
You'll make this change in your Google AI Studio account – the same place you got your special API key.
It might sound a bit technical, but it's like telling Google, "I'm happy to pay a few pennies for extra markings if I use up my 50 free ones." Here's the simple plan:
- Create a "Project": Inside Google AI Studio, it will guide you to create a 'Project'. Think of this as a special, named folder where your ClarkMark AI key will live.
- Enable Billing: You'll then "Enable Billing" for that project. This is where you securely add a payment method, just like adding a card to an Apple or Google Play account for buying apps or games.
- You're All Set! Once you've done that, your API key is automatically upgraded. The 50-per-day limit vanishes, and the super-speed is unlocked!
Google provides helpful pop-ups to guide you through each click. The most important thing to remember is that you only ever pay for what you actually use.