# Writing measurable acceptance criteria

Turn vague scope language into outcomes that an agency and client can review consistently.

Audience: Anyone preparing a milestone
Reading time: 9 min

## Use the ACT test


| Test | Question | Good signal |
| --- | --- | --- |
| Atomic | Does the criterion describe one outcome? | One pass or fail decision |
| Concrete | Can a client recognize the expected result? | Named page, action, value, or state |
| Traceable | Can it be tied to exact agreed language? | A precise SOW quote or approved amendment |

## A useful criterion formula


### Criterion formula

On [approved environment or page], when [authorized action or condition occurs], the product must [observable outcome] within/at [measurable threshold], as required by “[exact source quote].”

## Rewrite vague promises


| Vague | More measurable |
| --- | --- |
| The website will be responsive. | At 390 px viewport width, the approved pages have no horizontal overflow and the primary navigation remains operable. |
| The form should work. | Submitting valid name, business email, and message values creates the agreed success response without a client-visible error. |
| The site will be fast. | The agreed landing page meets the named performance threshold using the stated tool, device profile, and test conditions. |
| SEO will be implemented. | Each named indexable page has one unique title, one meta description, one H1, and the approved canonical URL. |
| The design will match the mockup. | The named components, content hierarchy, colors, type styles, and states match the approved design revision at the agreed viewports. |
| The site will be accessible. | The named pages and journeys pass the listed keyboard, labeling, focus, contrast, and automated checks in the agreed review scope. |

## Choose the right evidence


| Claim | Best evidence |
| --- | --- |
| Visible content or layout | Screenshot plus page URL and viewport |
| Navigation behavior | Recorded browser action and final URL/state |
| Form submission | Browser action plus observed network and success state |
| Client preference or subjective quality | Explicit client review decision |
| External business outcome | Authorized system record outside Greenlit |
| Compliance or certification | Qualified assessment, not a generic browser check |

## Final review questions

- Would two reasonable reviewers interpret the criterion the same way?
- Is the environment, page, action, threshold, or expected state named?
- Does the source quote actually support the criterion?
- Can Greenlit collect the required evidence safely and without unapproved side effects?
- Is a human client decision more appropriate than automation?
- Would changing this criterion after work is finished alter the agreed scope?