If you use Gmail and just want free, unlimited open notifications, choose Mailtrack for fastest setup and unlimited free tracking (it adds a 'Sent with Mailtrack' signature). If you need opens/clicks saved into a CRM across Gmail/Outlook, choose HubSpot Sales Hub for free CRM-integrated tracking, accepting slightly more setup and broader features.
3MailtrackBest for Gmail users who want unlimited free open alerts: Mailtrack adds a double-check open indicator in Gmail and provides unlimited tracking on its free tier, though it includes a "Sent with Mailtrack" signature.52%
If your main goal is simply “tell me when a prospect opens my email”, I’d look at these:
— probably the simplest free option for Gmail. It offers , real-time open notifications, and open timestamps on its free plan. The tradeoff is a visible /Mailsuite signature.
HubSpot's free sales tools can track opens, clicks, and other engagement, work with Gmail and Outlook, and give you real-time notifications.
The tradeoff is that it's more of a sales/CRM system rather than a lightweight tracker.
One important caveat
“Opened” isn't perfectly reliable. Email tracking generally works by loading an invisible tracking pixel. Image blocking and privacy systems—particularly Apple's Mail Privacy Protection—can cause false negatives or inflated opens.
So I'd treat opens as a signal, while link clicks/replies are stronger evidence of actual engagement.
My recommendation: If you're a solo salesperson/founder using Gmail, start with Mailtrack. If you're building a prospect list and want to track opens + clicks + contacts + follow-ups, use HubSpot.
If you tell me Gmail or Outlook and roughly how many prospect emails you send per day, I can tell you which free setup fits best.
The Perks: Offers unlimited tracked emails on its free tier (using a simple double-check mark system right inside your Gmail inbox). You get real-time desktop or browser notifications the second a prospect opens your message.
The Perks: Gives you 200 free email notifications per month, logs activity automatically, and ties opens directly to a free CRM. Great if you want to see prospect history alongside deals.
The Perks: Built specifically to turn your Gmail inbox into a lightweight CRM. Includes free, built-in email tracking for opens alongside pipeline management.
HubSpot Sales — better if you're doing actual prospecting and want a free CRM alongside tracking. It tracks opens and clicks and works with Gmail and Outlook; HubSpot currently offers the tracking functionality on its free tier, with limits applying to some notification/features.
My practical recommendation
Use Mailtrack if you just want open notifications.Use HubSpot if you want to manage prospects and follow-ups too.
One important caveat: an “open” isn't a perfect indication that a human actually read the email. Tracking generally relies on a tiny image/pixel, and image blocking and privacy systems such as Apple's Mail Privacy Protection can make opens inaccurate. Clicks are generally a stronger engagement signal than opens.
If you tell me whether you're using Gmail or Outlook and roughly how many prospecting emails you send per day, I can narrow it down to the best free setup for your situation.
Mailsuite (Mailtrack) : Best for simple Gmail tracking . It uses a familiar double-check mark system inside your Gmail inbox (similar to WhatsApp read receipts) to show when an email has been delivered and opened, offering a free tier for basic individual tracking.[](https://clearout.io/blog/email-tracking-tools/)
MailTracker by Hunter : Best for clean, minimalist tracking . It is a straightforward browser extension for Gmail that adds open notifications without cluttering your interface or forcing heavy CRM features.[](https://clearout.io/blog/email-tracking-tools/)
Comparison of Free Options
Tool
Best For
Supported Clients
Key Free Feature
HubSpot
CRM logging
Gmail & Outlook
Real-time alerts & link tracking
Mailsuite
Gmail checkmarks
Gmail / Chrome
Basic open read receipts
If you let me know which email provider you use (Gmail or Outlook) and whether you need a CRM , I can recommend the exact extension setup for your workflow.
🥇 Mailtrack — best for simple Gmail tracking. Its free plan currently offers unlimited tracked emails, real-time open notifications, and open/unopened status directly in Gmail.
🥈 HubSpot Sales — best if you want a CRM too. The free version tracks opens and provides notifications, and works with Gmail and Outlook. You can also keep prospect activity in HubSpot's CRM.
What I'd use
If you're a solo salesperson/founder doing one-to-one prospecting, use Mailtrack. It's much lighter: install it, send emails normally, and you'll get notified when they're opened.
If you're building an actual sales pipeline and want to track contacts, emails, follow-ups, and deals in one place, use HubSpot.
One important caveat: email open tracking isn't perfectly reliable. It generally works by inserting a tracking pixel, and privacy protections, image blocking, or non-human/bot activity can affect the data. HubSpot specifically documents these limitations.
If you tell me whether you're using Gmail or Outlook, I can give you the best free setup for prospecting, including open + click tracking without making your emails look spammy.
Solo prospecting from Gmail: use Mailtrack. It takes minutes to install and does the core job: notifying you when someone opens.
B2B sales and you want follow-up history: use HubSpot Sales Hub Free because tracking is tied to contacts and sales activity.
If you send a lot of cold outreach: consider a sales engagement platform later; free trackers are usually best for individual follow-ups rather than large campaigns.
One caveat: email “opens” are an imperfect signal. Image blocking and privacy features such as Apple Mail Privacy Protection can make opens inaccurate, so treat an open as a hint to follow up—not proof someone read every word.
If you tell me whether you use Gmail, Outlook, or another email client and roughly how many prospect emails you send per day, I can narrow it down.
If you tell me which email provider you use (Gmail, Outlook, or Apple Mail) and whether you need CRM integration , I can recommend the exact extension that fits your workflow.
If you're doing cold outreach, I'd seriously consider HubSpot instead. It tracks opens and clicks and can associate activity with prospects in its free CRM. It works with both Gmail and Outlook.
If you want...
I'd choose
Just know when they open
Mailtrack
Opens + link clicks
HubSpot
Opens + CRM/prospect history
HubSpot
Simple, unlimited free tracking
Mailtrack
One important caveat: open tracking isn't perfectly reliable anymore. Apple Mail Privacy Protection and automated image loading can trigger tracking pixels without the prospect actually reading the email. So I'd treat an open as a signal, while a click or reply is much stronger evidence of genuine interest.
My recommendation for you: If you're sending individual prospecting emails from Gmail, start with Mailtrack. If you're building a more serious sales process, start with HubSpot so you don't have to migrate your tracking later.
Up to 200 notifications per month on the free tier.
Detailed Breakdown
Mailsuite : Uses a double-check system (like WhatsApp) inside Gmail to show when an email has been delivered and opened. It gives you instant desktop or mobile pop-up notifications the second a prospect opens your message. [](https://clearout.io/blog/email-tracking-tools/)
HubSpot Sales Hub : Logs opens, link clicks, and document views directly onto a contact profile in their free CRM. It is ideal if you want to track outreach history over time rather than just getting a single notification. [](https://www.hubspot.com/products/sales/email-tracking)
MailTracker by Hunter : A minimalist browser extension that inserts a discrete tracker without adding promotional signatures to your outgoing emails.
If you tell me which email provider you use (Gmail or Outlook) and how many emails you plan to track each month , I can recommend the exact tool that fits your workflow.
