ibm-sg-numbers-and-measurement

IBM Style Guide: Numbers and Measurement review skill

Review documentation for number and measurement issues: numerals vs. words, formatting, currency, dates, times, units, and phone numbers.

Precedence: For Red Hat documentation, the Red Hat Supplementary Style Guide (SSG) takes precedence over IBM Style Guide rules. Where guidance conflicts, follow the RH SSG skill for that topic (e.g., rh-ssg-formatting for date formats).

Checklist

Numerals vs. words

• Zero through nine are spelled out; numerals are used for 10 and above
• Numerals are used with units of measurement: "5 GB," "3 seconds"
• Numerals are used in technical contexts: version numbers, port numbers, step counts
• Sentences do not start with a numeral (spell out or rewrite)
• All numbers in a series use numerals if any number is 10+: "3, 7, and 12 servers"
• Ordinals one through nine are spelled out; 10th and above use numerals

Number formatting

• Commas are used in numbers with four or more digits: 1,000 and 10,000
• A period is used for decimal points: 3.14
• Large round numbers use words: "2 million users" (not "2,000,000 users")
• Number ranges are consistent: "5 to 10" or "5-10," not "five to 10"

Currency

• ISO currency codes are used for international audiences: USD 100, EUR 50
• Currency symbols are used for domestic audiences: $100, €50
• Unnecessary decimal places are avoided: "$100" not "$100.00"
• Currency symbol or code is placed before the number

Dates and times

• Full date format is used for international clarity: "1 January 2025" or "January 1, 2025"
• All-numeric dates (01/02/25) are not used
• 24-hour clock is used for technical and international content: 14:00 (not 2:00 PM)
• Time zones are included when relevant: "14:00 UTC"
• ISO 8601 format is used in technical/data contexts: 2025-01-15T14:00:00Z

Units of measurement

• Standard abbreviations are used: KB, MB, GB, TB, ms, sec, min
• A space separates the number and unit: "500 MB" (not "500MB")
• IEC binary prefixes are used for binary values: KiB, MiB, GiB
• Abbreviated units are not pluralized: "5 GB" not "5 GBs"

Phone numbers

• International format with country code is used: +1 512 555 0100
• Parentheses around area codes are not used in international content

How to use

1. Review only changed content and necessary context
2. For each issue found, cite the relevant IBM Style Guide section
3. Mark issues as required (inconsistent formats, ambiguous dates) or [SUGGESTION] (preferences)

Example invocations

• "Review this file for number formatting issues"
• "Check dates and units in the release notes"
• "Do an IBM numbers review on modules/configuration.adoc"

References

For detailed guidance, consult:

• IBM Style Guide: Numbers and measurement sections