Surprising Psychology Behind Why Fundraising Thermometers Still Work + Helpful AI Boost

You’ve probably seen them.

The “old school” fundraising thermometer.

One of those things that makes you go… Hmmn…

Do those really work?

I’m bringing this up because…

• In his wonderful newsletter, Tom Ahern recently suggested reviving these.
• They’re also a technique favored by John Lepp, author of Creative Deviations. “Love them!” he says.

These fellows are true fundraising gurus, so (Hmmn…) this is worth your serious consideration!

Here’s what fundraising thermometers look like generally.

Visual Cues Inspire Donor Action

The thermometer is a simple visual representation of both the work completed and the work yet to be done.

Some think them “cheesy.” Or, as one of my former bosses used to admonish me, too “loving hands at home.” In other words, “unprofessional.”

Yet it turns out the perception of “professional” isn’t what moves people. Not at all. The stuff that sells is affective. It works on our emotions.

How it works is complex. Yet rest assured there are numerous scientific studies in a variety of disciplines (e.g., psychology, neuroscience, behavioral economics) that speak to the power of evoking certain decision-making shortcuts in your communications.

Want to get people to say “Yes” to your appeal? You need to push a few buttons. With intention.

Back to the thermometers. Whatever you or your powers-that-be may believe, the truth – based on science – is fundraising thermometers work. And I’d love to see you employ one this coming fundraising season.

So, let me explain to you why they work.

The Neuroscience of Nearly There: How a Thermometer Can Unlock Gifts

In 1934, American Psychologist Clark Leonard Hull proposed something that’s come to be called the goal-gradient effect It suggests individuals tend to increase their efforts as they get closer to a goal. It began with rats racing faster as they approached a food reward, yet the conclusion was ultimately that this effect applied to humans as well.

More recently, in 2006, Kivetz, Urminsky, & Zheng built on Hull’s hypothesis in their paper titled: The Goal-Gradient Hypothesis Resurrected: Purchase Acceleration, Illusionary Goal Progress, and Customer Retention. After conducting various field experiments, the authors made the following key findings:

1. 1. Participants in a Café reward program tended to purchase coffee more frequently as they approached earning a free drink.
   2. Internet users who rated songs in return for gift certificates visited the rating website more often, rated more songs than usual, and continued their rating efforts longer as they approached the reward.
   3. This phenomenon, known as “purchase acceleration”, is driven by the illusion of progress toward a goal or reward, encouraging faster buying behavior.
   4. A quicker movement towards a goal correlates with better retention and faster reengagement in a loyalty program.

In a 2009 study by Cryder, Loewenstein, & Scheines: The Critical Link Between Tangibility and Generosity, researchers also found goal proximity can lead to increased emotional response. Rates of donation increased as fundraising goals were approached. And disproportionate credit for campaign success was experienced (or anticipated to be experienced) by individuals who gave closer to the end of the campaign

TAKEAWAY: Efforts at the end of a process feel more concrete and influential than do efforts near the beginning of a process. If the perception of the reward is too distant, individuals are less likely to show goal-gradient behavior. The Cryder study found “the rate of contributions when recipients were 66-100% of the way toward reaching their fundraising goal was significantly and substantially greater.”

Other Decision-Making Shortcuts: How They Play With Thermometers

In 1984 Robert Cialdini wrote a groundbreaking book, Influence: The Psychology of Persuasion, outlining principles of influence that affect human behaviors. Trail-blazing research added by behavioral scientists like Daniel Kahneman and Amos Tversky supports and expands on Cialdini’s principles.

No matter how much technology advances, the triggers behind human behavior and decision making remain the same — and you can use them to your advantage!

TAKEAWAY: There’s nothing sleazy or manipulative about this. You’re simply speaking to the very human nature of humans – and that’s plain smart. You see, trying to persuade via facts, long-winded explanations and “educational” content just don’t work that well.  Humans are wired for other things. You need to design your fundraising appeals accordingly.

🧠💡Neuroscience, Psychology and the Science of Decision-Making

Tom Ahern and John Lepp helpfully summarize these five cognitive and behavioral-science principles for you, noting how they come into play with a thermometer. To quote John:

1. the ‘goal gradient effect’ > people are more motivated to take action as they approach a goal;
2. social proof/herd mentality > when you have a partially filled thermometer, it sends a signal that others have already taken this action to give and we naturally want to follow the crowd;
3. incompleteness effect > a partially filled thermometer triggers unease since incomplete tasks (or containers) are psychologically troubling;
4. anchoring effect > an almost full thermometer signals that just a little more is needed, making donating seem like an easy win;
5. scarcity and urgency > as the thermometer gets almost to the top, it visually signals the goal is in reach, which creates this “last chance” effect that encourages us to give before it’s too late.

💭💖Nostalgia

The fundraising thermometer is a classic. When you use a framework with which everyone is familiar, you evoke a sense of something old-school and trusted—which taps into nostalgia.

Nostalgia can be powerful in fundraising because it stirs emotions and creates a feeling of connection to tradition or shared history. Triggering old memories is similar to triggering mirror neurons. It taps into people’s emotions. Folks remember how they felt then, which acts as a shortcut to how you want them to feel now.

Even something as simple as a thermometer graphic can feel comforting or trustworthy, because it’s been around for decades.

Thermometers Can Be Used for Any Type of Fundraising Goal

For example:

• Year-end campaign
• Giving Tuesday campaign
• Project-specific campaign
• Deadline-specific campaign
• Peer-to-peer campaign
• Crowdfunding campaign
• Auction
• Special event

Display/embed your thermometer wherever folks are likely to see it.

For example:

• Your website homepage or event landing page.
• Your social media pages.
• Your email newsletter, with a link back to your campaign page.
• Your event space (for in-person fundraising events), such as a screen, including timely shoutouts when goals are met.
• Your organization’s office(s), so visitors and staff are inspired to continue working towards meeting your goal.

Ideally, it Should Update Automatically as New Gifts are Received

Some fundraising platforms include updating thermometers, so check with your vendor to see what they offer. You can also make a fundraising thermometer using a free or low-cost design software like Canva, Venngage or Adobe. Or you can grab a simple free template here.

Here are some examples of real-life fundraising thermometers:

KIVA automatically updating thermometers for different project campaigns

Plus, here are a bunch of thermometer ideas I found on Pinterest.

ACTION TIP: Consider  using a graphic that’s related to your cause (much like the Kingdom Animal Shelter graphic, above). Kindful recommends: “If you’re raising money to save the rainforest, create an image that includes a tree. If you’re building houses, choose a graphic that shows a house.” At an event, “if you’re holding a wine auction, you can use a wine glass or wine bottle. If you’re holding a baked goods drive, choosing a pie or cake might make sense.”

Get Creative to Use the Psychology Behind Fundraising Thermometers to Your Advantage.

I already hear you thinking… I don’t have time for this. So, just for fun, I asked ChatGPT to craft me a concept piece for a social justice organization. Why?  I’m trying to persuade you there’s simply no good excuse for not incorporating a thermometer into one of your upcoming campaigns.

Here’s what I got back – amazingly, in about five seconds!

“Tip the Scales of Justice” Fundraising Thermometer

🎯 Core Message

“Help us tip the scales of justice for those without a voice.”

🔍 Visual Design Concept

Graphic Style:
A set of balancing scales, one side weighted down with gold coins (representing systemic power and privilege), the other side slowly rising as donations increase—representing access to justice being restored through community support.

Dynamic Element:
As more donations are made, the “Justice” side of the scale fills with icons or figures symbolizing progress—like a gavel, a courthouse, a legal aid attorney, or even silhouettes of people standing up. Each donation adds symbolic weight, tipping the scale toward equity.

💡Layout Breakdown

Left Pan (Heavier Side – Injustice)

• Gray or black-toned.
• Visually overloaded with:
  • Dollar signs or gold coins.
  • Paper stacks representing bureaucracy.
  • A cracked gavel symbolizing broken justice.
  • The phrase: “Power. Privilege. Unchecked.”

Right Pan (Justice Side – Fundraising Meter)

• Brighter tone—using colors like blue or purple (associated with justice).
• As donations increase:
  • A progress bar subtly fills the pan.
  • Scale tilts more evenly, then begins tipping toward this side.
  • Milestones include:
    • 25%: “One person receives counsel”
    • 50%: “Systemic barriers challenged”
    • 75%: “Legal defense teams expanded”
    • 100%: “Scales tipped—Justice Served”

Supporting Text:

“Every gift adds weight to justice.”
“Every dollar brings us closer to a world where no one faces court alone.”

📱 How to Use This Concept

• On donation pages: Use an animated or interactive scale graphic to update in real time as the campaign progresses.
• In email and social media campaigns: Feature static versions of the scale with text overlay:
  “You helped tip the scales 47% closer to justice this week—thank you!”
• At live events: Create a physical installation of the scales. Add metal weights or cards with donor names as the campaign advances.

🎨 Customization Ideas

• If focusing on youth or immigrants, incorporate visuals like a backpack, courthouse steps, or family silhouette.

• You could swap coins for tokens of equity—like community hands or legal aid badges—if you prefer a more values-forward tone than material symbolism.

See what you can find for an organization like yours in 5 seconds! 

Sure, there’s work still to be done. But using AI prompts gives you a HUGE head start.

Consider a Fundraising Thermometer to Spur Year-End Giving

Hmmn…

Weren’t planning on using a thermometer?

Now, you know better.

Get creative, have fun, and super-charge your fundraising results!

Want More Year-End Fundraising Tips?

63 pages filled with year-end fundraising tips in this comprehensive Solution Kit

Get my Year-End Fundraising Solution Kit. It’s filled with tips and checklists to assure you don’t miss a trick. Everything you need to assure you get, and keep, the most donations possible this year. Not satisfied?  All Clairification products come with a 30-day, no-questions-asked, 100% money-back guarantee.

Image by Tumisu from Pixabay