AP Style Writing Numbers: Rules and Examples

Use words for zero to nine, and numerals for 10 and above

In AP style, most numbers are governed by a simple baseline: spell out numbers zero through nine, and use numerals for 10 and above. This rule supports readability at scale and is foundational for headlines, deck text, and body copy. For example, write "five people" and "15 teams." The approach applies across general contexts, including news desks and long-form content, where consistent treatment helps audiences scan and comprehend figures quickly.

Numerals for measurements and exact counts

Even below 10, use numerals when the context involves measurements, percentages, currencies, points on a scale, or precise data. This exception prioritizes clarity and comparability. Common scenarios include dimensions, speeds, temperatures, scores, rates, and financial figures. Pairing numerals with clear unit labels and standardized formats reduces ambiguity. For instance, write "5 kg," "98.6°F," or "$4.3 million," following conventions that technical, scientific, and commercial writing expect.

Beginning sentences and titles

Never start a sentence with a numeral. Reword or spell out the number to preserve a natural flow. For example, use "Twenty-two lawmakers voted" instead of "22 lawmakers voted." In subheadings, deck lines, and UI labels, recast phrasing to avoid leading digits when possible. This choice reflects AP guidance for headlines and entry-level metadata, reducing friction for readers and content systems that generate slug or title fields automatically.

Time, dates, and large approximate values

Decades and centuries

Write decades as numerals and lowercase, without apostrophs in standard AP usage. Use the 1900s format or early 1900s phrasing rather than the 1900’s style. Centuries are usually spelled out unless tied to precise years or formal names. For example, write "the 1990s" and "nineteenth century" to match reader expectations in historical or timeline contexts.

Dates and years

Use figures for dates and years, and include months for clarity when space allows. For example, write "March 15, 2023," or "15 March 2023" depending on regional conventions. Day-month-year ordering suits many international readers, while month-day-year is common in U.S. contexts. Keep styles consistent across datasets, CMS fields, and metadata schemas to simplify sorting and filtering.

Approximate sums and round numbers

Spell out round numbers that function as general references, such as "hundreds of attendees" or "thousands of reports." Use numerals when precision matters or when the figure appears in data rows, tables, or metrics-focused copy. This distinction helps editors balance narrative readability with analytical clarity. Context cues like "about," "roughly," or "nearly" often signal when an approximate tone justifies words instead of digits.

Large units, money, and percentages

For money, use numerals and standard symbols or codes, such as "$500," "USD 1.2 million," or "€75K." Avoid mixing formats within a section. For percentages, always use numerals with the % symbol, as in "98%" or "up to 50%," even when the value is below 10. For fractions, prefer simple styling like "one-half" or "50%" depending on whether you are emphasizing readability or precision.

Ordinal and nominal references

Spell out ordinal words in general prose, such as "first place" or "third quarter," while numerals are acceptable in lists, tables, and UI elements like "#1" or "Q3." Street addresses typically use numerals for the building number and words for street name, following local conventions and display constraints. Maintain stable addressing formats across records to support geocoding, routing, and data exports.

Editing practice and CMS considerations

Consistency is the highest editorial benefit when applying AP style writing numbers across headlines, metadata, and body text. Define number handling in style guides and component templates so fields such as year, price, or score behave predictably in search results and social previews. Use clear labeling, avoid ambiguous shortcuts, and validate numeric inputs during import to reduce rework and brand risk over time.

Summary of key AP style rules for numbers

These baseline expectations support long-term SEO durability, editorial clarity, and cross-platform consistency. By anchoring decisions in verifiable conventions, teams can maintain trustworthy, scannable content that performs well in search and content operations workflows.