Users of Certify'em are subject to usage quotas (limits) which affect how many responses and certificates Certify'em can process per day.
Please review the sections below to understand these limits, and whether or not Certify'em will meet your needs.
Daily Email Quota
Your daily email quota depends on which Certify'em plan you are using:
FREE: 60 email recipients per day
GOLD: Up to 400 email recipients per day*
PLATINUM: Up to 1500 email recipients per day**
Note that if you choose to send emails for exam attempts (an email is sent even when exam-takers don't pass), then those emails also count towards this limit. Certificates delivered to multiple recipients (via Cc or Bcc) also count towards this limit.
Exceeding this daily quota will affect the ability of Certify'em to send certificates until it is reset (once every ~24 hours).
* Requires that your account has access to Gmail (gmail.com). Without access you will be limited to 60 emails recipients / day, even with the GOLD or PLATINUM plan.
**The higher limit of 1500 email recipients / day requires a mature Google Workspace account (at least 60 days have passed since you have reached the $100 USD payment threshold). Prior to this your quota will be lower. If you do not have a Workspace account (i.e. you have a regular @gmail.com account) then you will be limited to 400 email recipients / day (same as GOLD plan).
Daily Server Quotas
Users of Add-ons like Certify'em can be subject to other daily quotas from Google too. These quotas are imposed by Google, and not by Certify'em. These are related to factors like total processing time per day, total database accesses per day, usage of Google Drive services, etc. Exceeding these quotas will also affect the ability of Certify'em to process responses and send certificates until they are reset by Google (every ~24 hours).
What Happens If I Exceed a Quota?
When you surpass a daily quota, Certify'em can no longer process Google Form responses and send emails to exam-takers. To avoid the confusion this may cause, Certify'em will try to automatically turn OFF certification and disable access to your exam if it detects you've exceeded any of these daily quotas. This is to ensure that exam-takers can always receive a certificate if they take your exam. Users visiting your exam will see a message like "This form is no longer accepting responses". Additionally, you will not be able to resend certificates manually until the quotas have reset.
Quotas are reset approximately every 24 hours. After turning certification OFF in your exam, Certify'em will check back every hour until these quotas have reset, at which point it will try to turn certification ON and and reenable exam access. You will not be notified again by email when certification is turned back ON.
Even once your daily quotas have been restored, any Google Form responses made while quotas were exceeded will not be automatically reprocessed by Certify'em. You will instead need to reprocess these using the Resend Certificates functionality of Certify'em.
Can My Daily Quotas Be Increased?
Daily email quotas can be increased by purchasing a Gold or Platinum plan.
Daily server quotas are set for Add-ons by Google, not Certify'em, so unfortunately they cannot be increased.
If you need to send more certificates each day than you can now, here are a few options for you to consider:
Share via Drive: Instead of emailing certificates, consider the option to share via Google Drive (see advanced options). This works because the email notifications are sent by Google Drive, and not Certify'em. Exam-takers will also be able to find their certificates in the "Shared with me" section of their Google Drive. Note though that:
Google Drive has its own quotas (see Daily Server Quotas above), and while you may be able to share more certificates with this method compared to email, you may still reach a daily limit.
Recipients will need a Google account (i.e. Google Workspace or @gmail.com) to be able to print or download the certificate. Else they will only be able to view the file and will have to take a screenshot.
Use multiple accounts: If you have more than one exam, you could consider setting up a dedicated @gmail.com account for each exam. This does not change the daily quota set by Google, but would allow each exam (account) to take full advantage of it.
Setup a Google Workspace account: If you are using personal Gmail, you are limited to 60 emails/day with Certify'em FREE and 400 email recipients / day with Certify'em Gold. In contrast, a Certify'em Platinum plan in combination with a mature Google Workspace account has a much higher limit of 1500 email recipients / day. Note that:
Google Workspace is not free in most circumstances.
Plan on setting aside a few hours to purchase and setup Google Workspace.
The higher per day email limits for Google Workspace accounts won't take effect until (1) your Workspace domain has cumulatively paid Google at least USD $100 (or equivalent), and (2) at least 60 days have passed since reaching that payment threshold. You will need to plan for this time, and/or pay the $100 USD (or equivalent) early. See this article for more on paying early.
Even when setup properly, for new Google Workspace domains it can take at least 60 days before Google stops treating emails sent by Add-ons (like Certify'em) with more strict SPAM filters. Ergo, emails with certificates send outside of your Google Workspace domain may bounce back during this time.
You should read this article carefully for a more detailed discussion of using Google Workspace.