Are the calculators free to embed?

Yes. All five are free to embed on any website, with no sign-up, no API key, and no usage limit. The only condition is keeping the small attribution link that comes with the embed code.

Do I need any code skills or a plugin?

No. The embed is a single line of HTML (an iframe). Paste it into your page wherever you want the calculator to appear. No JavaScript, plugin, or account needed. You can also send the code to your web developer to implement.

How do I embed it on WordPress, Squarespace, or Wix?

WordPress: paste it into a Custom HTML block. Squarespace: a Code block. Wix: an Embed / HTML iframe element. Webflow: an Embed element. Any plain HTML page: paste it into the page body.

Can I change the size or style?

You can adjust the width and height in the snippet to fit your layout, and it is responsive on mobile. The calculator's own styling stays fixed so it remains consistent and on-brand wherever it appears.

What data do the embedded calculators collect?

None. Each calculator runs entirely in the visitor's browser and stores nothing. There are no ads and no third-party tracking inside the embedded widget.

Which calculators can I embed?

All five: fitness age, VO2 max, grip strength, waist-to-height ratio, and the sitting-rising test. Each is benchmarked to a named primary source (the FRIEND registry, the Asian Working Group for Sarcopenia, and Ashwell's waist-to-height work).

Free Tools

Embed our free health calculators

Every Catalyst calculator is free to embed on your website. One line of code, no sign-up, no API key, no cost. Each one is evidence-based and benchmarked to the reference standards, runs entirely in the visitor's browser, and collects no data. Paste the snippet yourself or send it to your web developer.

Quick answer

You can embed any of Catalyst Performance's five free health calculators, fitness age, VO2 max, grip strength, waist-to-height ratio, and the sitting-rising test, on any website with a single line of HTML. They are free, require no account or API key, work on mobile, and collect no visitor data. Each embed includes a small attribution link back to Catalyst Performance.

How to embed a calculator

1
Copy the embed code
Pick the calculator you want below and click Copy to grab its one-line embed code.
2
Paste it into your page
Paste the code into your page's HTML where you want the calculator to appear, using a Custom HTML / Code / Embed block on most site builders.
3
Publish
Publish the page. The calculator loads instantly, works on mobile, and collects no data. The attribution link is already included.

The five calculators

Copy a snippet and paste it into your page. Preview each tool before you embed it.

Fitness Age Calculator

Preview the tool →

Estimates the age at which someone's cardiorespiratory fitness would be average, from their resting heart rate.

<iframe src="https://catalystperformance.sg/embed/fitness-age" width="100%" height="640" style="border:0;max-width:680px" loading="lazy" title="Fitness Age Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/fitness-age">fitness age calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

VO2 Max Calculator

Preview the tool →

Shows a VO2 max percentile for age and sex against the FRIEND registry, or estimates it from resting heart rate.

<iframe src="https://catalystperformance.sg/embed/vo2-max-calculator" width="100%" height="720" style="border:0;max-width:680px" loading="lazy" title="VO2 Max Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/vo2-max-calculator">VO2 max calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Grip Strength Test

Preview the tool →

Checks handgrip against the AWGS sarcopenia thresholds and age-and-sex percentiles.

<iframe src="https://catalystperformance.sg/embed/grip-strength-test" width="100%" height="680" style="border:0;max-width:680px" loading="lazy" title="Grip Strength Test by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/grip-strength-test">grip strength test</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Waist-to-Height Ratio Calculator

Preview the tool →

Flags cardiometabolic risk against the 0.5 waist-to-height boundary.

<iframe src="https://catalystperformance.sg/embed/waist-to-height-ratio" width="100%" height="680" style="border:0;max-width:680px" loading="lazy" title="Waist-to-Height Ratio Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/waist-to-height-ratio">waist-to-height ratio calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Sitting-Rising Test

Preview the tool →

Scores the floor sit-to-stand test out of 10, a no-equipment stability and mortality-linked measure.

<iframe src="https://catalystperformance.sg/embed/sit-rise-test" width="100%" height="700" style="border:0;max-width:680px" loading="lazy" title="Sitting-Rising Test by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/sit-rise-test">sitting-rising test</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Embedding, common questions

Are the calculators free to embed?: Yes. All five are free to embed on any website, with no sign-up, no API key, and no usage limit. The only condition is keeping the small attribution link that comes with the embed code.
Do I need any code skills or a plugin?: No. The embed is a single line of HTML (an iframe). Paste it into your page wherever you want the calculator to appear. No JavaScript, plugin, or account needed. You can also send the code to your web developer to implement.
How do I embed it on WordPress, Squarespace, or Wix?: WordPress: paste it into a Custom HTML block. Squarespace: a Code block. Wix: an Embed / HTML iframe element. Webflow: an Embed element. Any plain HTML page: paste it into the page body.
Can I change the size or style?: You can adjust the width and height in the snippet to fit your layout, and it is responsive on mobile. The calculator's own styling stays fixed so it remains consistent and on-brand wherever it appears.
What data do the embedded calculators collect?: None. Each calculator runs entirely in the visitor's browser and stores nothing. There are no ads and no third-party tracking inside the embedded widget.
Which calculators can I embed?: All five: fitness age, VO2 max, grip strength, waist-to-height ratio, and the sitting-rising test. Each is benchmarked to a named primary source (the FRIEND registry, the Asian Working Group for Sarcopenia, and Ashwell's waist-to-height work).

More from Catalyst

Catalyst Performance

Embed our free health calculators

Quick answer

How to embed a calculator

1
Copy the embed code
Pick the calculator you want below and click Copy to grab its one-line embed code.
2
Paste it into your page
Paste the code into your page's HTML where you want the calculator to appear, using a Custom HTML / Code / Embed block on most site builders.
3
Publish
Publish the page. The calculator loads instantly, works on mobile, and collects no data. The attribution link is already included.

The five calculators

Copy a snippet and paste it into your page. Preview each tool before you embed it.

Fitness Age Calculator

Preview the tool →

Estimates the age at which someone's cardiorespiratory fitness would be average, from their resting heart rate.

<iframe src="https://catalystperformance.sg/embed/fitness-age" width="100%" height="640" style="border:0;max-width:680px" loading="lazy" title="Fitness Age Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/fitness-age">fitness age calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

VO2 Max Calculator

Preview the tool →

Shows a VO2 max percentile for age and sex against the FRIEND registry, or estimates it from resting heart rate.

<iframe src="https://catalystperformance.sg/embed/vo2-max-calculator" width="100%" height="720" style="border:0;max-width:680px" loading="lazy" title="VO2 Max Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/vo2-max-calculator">VO2 max calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Grip Strength Test

Preview the tool →

Checks handgrip against the AWGS sarcopenia thresholds and age-and-sex percentiles.

<iframe src="https://catalystperformance.sg/embed/grip-strength-test" width="100%" height="680" style="border:0;max-width:680px" loading="lazy" title="Grip Strength Test by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/grip-strength-test">grip strength test</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Waist-to-Height Ratio Calculator

Preview the tool →

Flags cardiometabolic risk against the 0.5 waist-to-height boundary.

<iframe src="https://catalystperformance.sg/embed/waist-to-height-ratio" width="100%" height="680" style="border:0;max-width:680px" loading="lazy" title="Waist-to-Height Ratio Calculator by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/waist-to-height-ratio">waist-to-height ratio calculator</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Sitting-Rising Test

Preview the tool →

Scores the floor sit-to-stand test out of 10, a no-equipment stability and mortality-linked measure.

<iframe src="https://catalystperformance.sg/embed/sit-rise-test" width="100%" height="700" style="border:0;max-width:680px" loading="lazy" title="Sitting-Rising Test by Catalyst Performance"></iframe>
<p style="font-size:13px;line-height:1.5;text-align:center;margin:8px 0">Free <a href="https://catalystperformance.sg/tools/sit-rise-test">sitting-rising test</a> by <a href="https://catalystperformance.sg">Catalyst Performance</a>, a longevity-focused personal training studio in Singapore.</p>

Embedding, common questions

Are the calculators free to embed?: Yes. All five are free to embed on any website, with no sign-up, no API key, and no usage limit. The only condition is keeping the small attribution link that comes with the embed code.
Do I need any code skills or a plugin?: No. The embed is a single line of HTML (an iframe). Paste it into your page wherever you want the calculator to appear. No JavaScript, plugin, or account needed. You can also send the code to your web developer to implement.
How do I embed it on WordPress, Squarespace, or Wix?: WordPress: paste it into a Custom HTML block. Squarespace: a Code block. Wix: an Embed / HTML iframe element. Webflow: an Embed element. Any plain HTML page: paste it into the page body.
Can I change the size or style?: You can adjust the width and height in the snippet to fit your layout, and it is responsive on mobile. The calculator's own styling stays fixed so it remains consistent and on-brand wherever it appears.
What data do the embedded calculators collect?: None. Each calculator runs entirely in the visitor's browser and stores nothing. There are no ads and no third-party tracking inside the embedded widget.
Which calculators can I embed?: All five: fitness age, VO2 max, grip strength, waist-to-height ratio, and the sitting-rising test. Each is benchmarked to a named primary source (the FRIEND registry, the Asian Working Group for Sarcopenia, and Ashwell's waist-to-height work).