- What are subject line testers and headline analyzers?
- What are some popular subject line testers?
- Are there any popular free headline analyzers?
- How do I use subject line testers and headline analyzers?
- Are they effective?
- What about headline analyzers? Are they any more accurate?
- Should I use subject line testers and headline analyzers?
- What other tools can I use to analyze subject lines and headlines?
Do you write marketing emails for work or to promote your brand? If so, you probably care about open rates. When it comes to email, subject lines are crucial. If people don’t open your email (or mark it as spam), it doesn’t matter how awesome your email is.
The same goes for webpage and blog headlines. If they don’t grab people’s attention, especially on a search results page, your content doesn’t matter. It’s no wonder many people use subject line testers and headline analyzers.
I’ve seen this stat many times—you should spend half your time on your subject line. Why? It’s just a few words. Isn’t the email content more important? Only if people open your email. That’s why so many copywriters spend so much time on email subject lines and blog headlines. It’s also why so many use subject line testers to try and gain an edge.
Headline analyzers have become popular for a similar reason. Your page is competing with 100s of others, but you want people to click your link. You need to stand out.
I’ve got over a hundred blogs on my site. My top-performers have thousands of views. But others are in single digits. Part of that is due to how high (or low) those pages appear in Google search results. But it’s also down to how enticing those blog titles are to potential readers.
What are subject line testers and headline analyzers?
Subject line testers are tools that review your subject line and give it a score. The higher the score, theoretically, the more likely people are to open your emails. Different tools rate your subject line against various metrics. They look at things such as
- Reading grade level (lower is usually better)
- Length (characters and/or words)
- Sentiment (positive, negative, urgent, neutral)
- Potentially spammy/negative words (free, hurry, cash)
- Copywriting “tricks” (phrased as a question, contains numbers, emojis included)
- Positive/Power words (insights, profound, resonate)
- Case (sentence case vs. title case)
- Personalization
Not every subject line tester checks for everything. Many assign greater importance to certain areas than others. Further complicating matters, what one tool considers a “spammy word,” another considers a “power word.”
Some don’t provide any analysis, but just give you a score. Many give you a breakdown of the pros and cons of your subject line. Others provide AI-based alternatives or suggestions for improvements.
Headline analyzers are very similar. They score your headlines against several different categories. And again, each one assesses different things and attaches different weights to different areas.
So if they all test for different things and don’t use the same scoring rubric, how do you know which one to use? The short answer? Don’t use just one—but more on that later.
What are some popular subject line testers?
Try Googling “subject line testers” (you may want to include “free” in that search). These are likely to be on the first page. I’ve been using them for several years now.
I’m sure there are others, and if you have a favourite, please leave a comment and let me know. One of the biggest challenges with subject line testers and headline analyzers is that they use different scales. You’re comparing apples and oranges. For example, Send Check It and SubjectLine.com will give you scores that can vary by as little as 1 point. But Omnisend only offers scores of
- 100
- 92
- 83
- 75
- 67
- 58
- 33
Additionally, none of these subject line testers check for spelling, grammar or logic. For example, here are their scores for “Great subject line score 99% you, right?”
- Send Check It—99
- SubjectLine.com—91
- Omnisend—67
- mailmeteor—71
These are free tools, but like most tools, they’re only as good as the people using them. That gibberish subject line has many things these subject line testers look for:
- Phrased as a question
- Contains a number
- Personalization (you)
- Power word (Great—better than good)
But I doubt that a subject line like that would perform well—it’s gibberish.
Are there any popular free headline analyzers?
I’ve previously written about one of the most popular headline analyzers, Coschedule’s Headline Studio. But the free version now limits you to 10 free headline analyses/month. So, I reserve that for my personal blogs. For my work, I’ve had to find other free headline analyzers. Here are four popular ones I’ve started using.
They suffer from the same shortfalls as subject line testers. They use different scales. Most are only looking for words and patterns, not grammatically correct phrases. Here are the results for “Best tool results analyzer headline excellent.”
- AIOSEO— 92
- MonsterInsights—92
- isitwp—92
- sharethrough—15
FWIW, AIOSEO states that a score between 60-80 is a good score, but recommends striving for 70 or higher. For MonsterInsights, a score of 40–60 is considered good, but you should aim for 70 or higher. In my testing, I’ve noticed that the first three sites tend to give either the same (or very similar) scores. But note the extremely low score from sharethrough. It picked up on the fact that this makes no grammatical sense.
That’s a positive. But again, use these tools with caution. If you’re a non-native English speaker, sharethrough might be a useful option. Or you could contact DC CopyPro. 😉
How do I use subject line testers and headline analyzers?
Earlier, I posed the question, “How do you know which one to use?” And my answer to that was, “Don’t use just one.” So, how do you use multiple ones?
I’ve set up a spreadsheet where I can record the scores for each subject line tester or headline analyzer. I take the averages of those scores, and then I sort them from highest to lowest. I also average the scores for each column to see trends. When it comes to subject line testers, I can see that Send Check It tends to score higher than the others. Subjectline.com is in the middle, while Omnisend and MailMeteor have similar average scores.
For headline analyzers, I use the same format. As alluded to before, AIOSEO, MonsterInsights, and isitwp are typically around the same. Sharethrough averages roughly 17 points higher.
By averaging the scores together, I get an overall score. This is important because, as mentioned, each one prioritizes different areas.
Bonus tip: I’ve recently switched to the Vivaldi browser. I made the switch after my browser of choice, Sidekick, stopped being supported. One of Vivaldi’s features that I love is the ability to tile tabs. I then set up a workspace with those four tabs in my desired layout. I just open my spreadsheet for scoring subject lines and headlines in one window. Then I open my subject line scoring workspace (or headline scoring workspace) in another tab. This makes it quick and easy to test each subject line with each tool and tweak it to achieve the best results.
Saving these tabs in the same layout (as below) is a real time-saver. It’s very convenient for testing several subject lines or headlines quickly.
Are they effective?
So, now you know what subject line testers and headline analyzers are. You also know what they check and how you can use them to score your subject lines and headlines. But do they work? Let’s find out.
I send several marketing emails each month as part of my job. We recently decided to compare the scores from these subject line testers against our email open rates. I analyzed 70+ subject lines and their corresponding open rates. I then asked ChatGPT to analyze the data and look for trends in subject line styles. Additionally, I asked ChatGPT whether any of the subject line testers were more reliable than the others. Finally, I wanted to know if the average score had any correlation with the open rate.
I’ve had to anonymize the subject lines, but we can still learn several things. Rather than reviewing all the subject lines, I decided to highlight the top and bottom five. First, I sorted the top five and bottom five by open rate.
You can see the top 5 were all above 30%, which is a pretty respectable open rate. The bottom five were quite low, some dipping into single digits.
However, what happens when we sort them by average score from the four subject line testers?
Interesting. Despite seemingly high average scores, the highest open rate for the top five is only 24%. And then when we look at the lowest-scoring subject lines, three of them have higher open rates above 24%.
This aligns with ChatGPT’s analysis. It found no correlation between average scores and open rates. Additionally, none of the subject line testers were more accurate than the others.
What about headline analyzers? Are they any more accurate?
For this, I chose to use my own data from my website. Rather than report on all 100 of my blogs, I focused on the top and bottom five. But out of interest, I also chose to include my most recent blog. Here are my top and bottom five performing blogs based on the total number of views.
Since it often takes time to accumulate views, I have also included the age of each blog for reference. My top-performing blog has a relatively high average score from the headline analyzers. The rest of the top five is a mixed bag. Two of the average scores are actually below the average score for all 10 blogs. Furthermore, if you look at my third-worst-performing blog, it has an average score of 91. That’s the highest average score.
Note that three headline analyzers returned the same score for seven headlines. And sharethrough had a lower score than the other three twice (1 & 8). And in five instances, it returned a score more than 10 points higher than the other three.
What happens when we sort by average score?
The top-scoring headline is my third-worst-performing blog. It’s only been live for 4 months, but for such a high-scoring headline, you’d expect better performance. Even last week’s blog is already 17 spots higher than my third-worst-performing blog. And that’s despite having an average score that’s just outside my five worst-performing blogs.
Should I use subject line testers and headline analyzers?
Yes—as a tool. They’re part of the equation, but they’re not the definitive answer. Subject line testers and headline analyzers help me come up with alternatives. Often, they provide angles I may never have considered. But I don’t automatically choose the highest-scoring subject line. The scores may influence my decision, but the choice is always mine.
As previously mentioned, I also use CoSchedule Headline Studio for my personal blog posts. So, how did I arrive at the title of this blog? I started with a base idea and then attempted to incorporate some suggestions from various tools. Here’s how things scored, including the Coschedule score.
I decided to go with the top average-scoring one (not including Coschedule). The second option scores much higher on Coschedule. But I just like how the first one flowed and sounded. It
- Contained my key phrase.
- Mentioned my topic.
- Was phrased as a question (often an effective tactic for drafting headlines).
What other tools can I use to analyze subject lines and headlines?
Don’t just rely on these subject line testers and headline analyzers. Track your own stats and review them. Draw your own conclusion by analyzing subject lines. Review ones that perform exceptionally well and ones that don’t. Do the same with your best- and worst-performing blogs.
Occasionally, check if ChatGPT can provide any insights. When I used ChatGPT to analyze our subject lines, it didn’t give me the answers I was looking for. Although it didn’t find any correlations between scores and open rates, it was still helpful. It provided me with some valuable feedback on which topics and types of subject lines were effective. For example, I learned that “clever” subject lines and emojis don’t work for our audience.
So, are you going to start using subject line testers and headline analyzers? Or will you stop using them after reading this blog? Please share any tools you use to help with drafting subject lines and headlines in the comments. I’m always eager to explore new tools.
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It’s always a pleasure to read your blogs; they serve as reminders, guidelines, and inspiration. My blogs appear now in Google more often than the main pages. I need to step up the game for landing pages. 😇
As always, thanks for the support, Cristian. I’m glad you still enjoy reading my ramblings. 😉
Of course.