The rule: define it first
Every major style guide (APA, Chicago, the AMA Manual, most government and corporate guides) asks writers to spell out an acronym or initialism the first time it’s used, followed by the short form in parentheses: “World Health Organization (WHO)”. After that, the short form can stand alone. Readers who join mid-document, translate the text or aren’t specialists depend on it.
What the checker reports
The checker finds every acronym (two or more capitals, optionally with digits or &, plus plurals like APIs) and looks for a definition in either form:
- Full Name (ABC): the words before the parentheses must start with the acronym’s letters (small words like of, and and the can be skipped);
- ABC (Full Name).
Each acronym is then classed as defined, never defined, or used before its definition. The highlights show the first problematic use in your text, and the table lists every acronym with how often it appears (a ready-made list of abbreviations for a report or thesis).
Very common ones (US, UK, EU, PDF, URL, CEO…) are skipped by default; turn that off for formal or international documents. Roman numerals and sentences written entirely in capitals are ignored.
Worked example
Here is what the Acronym Checker returns for its built-in example. Settings used: Skip very common ones (US, PDF, CEO…): on. Click Try an example in the tool above to load it, then change it as you like.
The WHO and the CDC published new guidance. The World Health Organization (WHO) recommends regular review. Our KPI targets follow the Service Level Agreement (SLA). The SLA is reviewed yearly, and the API documentation explains the rest.| Found | Type | Suggestion |
|---|---|---|
| “WHO” | Used before definition | — |
| “CDC” | Never spelled out | — |
| “KPI” | Never spelled out | — |
| “API” | Never spelled out | — |
Questions
Do I need to define acronyms like NASA?
Style guides usually exempt acronyms that readers know better than the full name (NASA, FAQ). Check your guide; this tool skips a list of very common ones by default.
Can I generate a list of abbreviations for my thesis?
Yes. The table lists every acronym with its definition, which you can copy into a list of abbreviations.
Last reviewed · How Textkiln tools work