For each image used as a CAPTCHA, is an alternative way to access the content or function of the CAPTCHA available?
A blind user knows a CAPTCHA is present — their screen reader will announce 'Enter security code' if you have correctly filled in the alt attribute (criterion 1.4). But knowing it exists is not enough: you still need to be able to solve it. A visual CAPTCHA without an alternative is a locked door.
Criterion 1.5 requires that for each image CAPTCHA there is at least one other way to access the protected functionality. This alternative can be a non-graphical CAPTCHA (audio challenge, mathematical question, logical question) or an entirely different mechanism allowing you to accomplish the same action without going through the visual challenge (contact with a human operator, account-based authentication).
Do not confuse 1.4 and 1.5. Criterion 1.4 requires that the CAPTCHA image carry an alt describing its purpose. Criterion 1.5 requires that an alternative to the challenge itself exists. You can have a flawless alt and fail 1.5 if no other way is offered. In audits, both criteria often fail simultaneously.
2 tests to confirm that an alternative access to CAPTCHA is offered
Non-graphic alternative to image CAPTCHA
- Identify all
<img>,<area>,<object>,<embed>,<svg>,<canvas>elements or those bearingrole="img"that serve as CAPTCHA or test images on the page. - For each one, verify that at least one of the following two conditions is met :
- A non-graphical CAPTCHA is offered (audio challenge, mathematical question, logical question), or
- Another way to access the secured functionality is available (contact form, phone number, account-based authentication).
- If no alternative is present for at least one of these elements, the test fails.
Non-graphic alternative to CAPTCHA <input type="image">
- Identify all
<input type="image">elements used as CAPTCHA or test images on the page. - For each one, verify that at least one of the following two conditions is met :
- A non-graphical CAPTCHA is offered (audio challenge, mathematical question, logical question), or
- Another way to access the secured functionality is available (contact form, phone number, account-based authentication).
- If no alternative is present for at least one of these image buttons, the test fails.
Examples
❌ Non-compliant : Visual CAPTCHA with no alternative
<form action="/inscription" method="post">
<label for="email">Email address</label>
<input type="text" id="email" name="email">
<img src="/captcha/generer" alt="Security code to enter">
<label for="code-captcha">Enter the code displayed</label>
<input type="text" id="code-captcha" name="captcha">
<button type="submit">Create my account</button>
</form>The image does have an alt — criterion 1.4 is met. But there is no alternative to the visual challenge itself. A blind user or user with severe visual impairment cannot decipher the distorted image and finds themselves unable to create an account. Criterion 1.5 fails.
✅ Compliant : Visual CAPTCHA with audio alternative and operator access
<form action="/inscription" method="post">
<label for="email">Email address</label>
<input type="text" id="email" name="email">
<img src="/captcha/generer" alt="Visual security code">
<label for="code-captcha">Enter the code displayed</label>
<input type="text" id="code-captcha" name="captcha">
<a href="/captcha/audio">Listen to the audio code instead</a>
<p>
Cannot solve this challenge?
<a href="/contact">Contact our team to create your account</a>.
</p>
<button type="submit">Create my account</button>
</form>Two alternatives are offered: an audio CAPTCHA (non-graphical challenge) and a link to a human operator. A blind user will choose audio; a deafblind user can contact the team. Each disability profile has a real access path. Criterion 1.5 is validated.
Tips and pitfalls
⚠️ Confusing criterion 1.4 and criterion 1.5
Criterion 1.4 concerns the text alternative on the CAPTCHA image (the alt that describes its function). Criterion 1.5 concerns an alternative to the challenge itself. You can have perfect alt text and still fail 1.5 if no other access path exists. In audits, both criteria often fail simultaneously — but they must be corrected separately.
⚠️ An audio CAPTCHA alone does not cover all profiles
An audio challenge is a valid alternative for blind users, but not for deafblind users or those without audio output available. To cover all profiles, combine audio challenge and access via human operator (contact form, email address, phone number).
💡 Removing the CAPTCHA is also a valid alternative
The WCAG explicitly acknowledges this: if you replace a visual CAPTCHA with an invisible mechanism (honeypot, behavioral analysis, server-side rate limiting, mCaptcha), there is no longer a challenge to make accessible. Cloudflare Turnstile, for example, operates via a background JavaScript challenge without ever displaying an image to decipher. This is the cleanest solution, and it satisfies 1.5 by design.
⚠️ <input type="image"> used as CAPTCHA
This is rare but it happens: some legacy systems use an image button to submit a CAPTCHA code. Test 1.5.2 specifically covers this case. The alternative requirements are identical to 1.5.1 — the difference is only in the type of HTML element to inspect during the audit.
⚠️ Non-graphical CAPTCHAs are not covered
Criterion 1.5 applies only to image-based CAPTCHAs. A logic question ('What is 3 plus 4?') or a purely text-based CAPTCHA does not require an alternative in the sense of this criterion — you are already in the solution.
Frequently asked questions
Why is Google reCAPTCHA v2 often not compliant with criterion RGAA 1.5?
Not automatically. reCAPTCHA v2 sometimes displays an image grid to identify (traffic lights, pedestrian crossings). If this grid appears, it is a visual CAPTCHA that must have an accessible alternative. Google offers an accessibility mode with audio challenge, but you must verify that this mode is enabled and functional in your implementation. reCAPTCHA v3, which operates in the background without visible interaction, is preferable from the perspective of criterion 1.5.
Why is a 'Contact us' link not enough as a CAPTCHA alternative compliant with RGAA?
Yes, provided it actually allows you to accomplish the same action as the one protected by the CAPTCHA. If the CAPTCHA protects a registration form, the contact link must enable account creation via a human operator. A link to the home page or to a general FAQ does not constitute a valid alternative.
How to identify non-compliant CAPTCHAs during an RGAA accessibility audit?
Look for <img>, <svg>, <canvas>, role="img" and <input type="image"> elements that accompany a code input field or that are part of a secured form. Disabling images in the browser (Firefox: Tools → Options → Content) helps visually isolate CAPTCHA areas. For each one, test whether the page offers another path to submit the form without solving the graphical challenge.
How does criterion RGAA 1.5 apply to third-party CAPTCHAs integrated via iframe?
Yes. Responsibility lies with the website owner, not the component provider. If you integrate hCaptcha or reCAPTCHA via an iframe, you must ensure that the provider offers an accessible mode and that this mode is enabled in your configuration. If this is not possible, add your own alternative outside the iframe — a link to a contact form, for example.