{"calculator":{"slug":"fat-hand-time-converter","math":{"href":"https://www.tracktoolspro.com/api/calculators/fat-hand-time-converter","jsonPointer":"/calculator/math","version":"2026-10-21.1","implementationVersion":"b5a8aca7b85361476e0321a08b7fa5f516fc9535","scope":"Canonical HTTP function and documented corresponding mounted-form math. This is public inspectable documentation, not access control or independent empirical validation.","unitNotation":"Input paths use [] and *; output paths are JSON Pointers with * (one segment) and ** (descendants). Empty output path denotes scalar result. Units apply to numeric quantities or explicitly described numeric strings; labels/statuses/booleans are dimensionless. More specific units, including count/index exceptions, override broad patterns.","interfaceNotes":["HTTP input is described by the adjacent inputSchema. The original handlers may accept numeric strings; this metadata adds no validation.","Mounted forms accept displayed clock/unit strings and enforce their own limits. Mounted tools limit strings to 200 characters and numeric parts to magnitude 1000000. Do not assume mounted/API input interchangeability.","Some legacy extreme/invalid tuples can produce null/empty results or nonfinite numbers serialized as null. Those are unavailable answers, not exact numerical predictions. Per-calculator domain describes the intended mathematical inputs."],"kind":"rule-convention","implementationFiles":["lib/formulas/fat-hand-time.ts"],"equations":["NFHS offset=0.24s for all retained categories; WA combined offsets: sprint(<400m)=0.24, middle(400m)=0.14, long(>400m)=0.","handToFat: upward round manual time to the next tenth only if not already exactly at a tenth, then add offset and round nearest hundredth. fatToHand: subtract offset, then round nearest hundredth."],"inputUnits":{"timeSeconds":"s","direction":"enum/string (dimensionless)","eventCategory":"enum/string (dimensionless)","convention":"enum/string (dimensionless)"},"outputUnits":{"/originalTime":"s","/convertedTime":"s","/factor":"s","/roundedHandTime":"s"},"domain":["Positive finite input and positive converted result; otherwise null. convention defaults to nfhs."],"rounding":["Forward manual ceil-to-tenth with binary guard, then Math.round(x*100)/100. Reverse only nearest0.01."],"assumptions":["Uses the entered values and the selected convention; this documentation does not strengthen existing validation."],"limitations":["Reverse is an estimate: it cannot recover the original manual reading after upward rounding. These named conventions are not universal record conversions."],"mountedPageNotes":[],"workedExamples":[{"input":{"timeSeconds":10.8,"direction":"handToFat","eventCategory":"sprint"},"expected":{"/convertedTime":11.04},"absoluteTolerance":1e-8,"note":"Illustrative canonical-handler result; not independent validation of an empirical model."}],"constantsAndTables":{"nfhsOffsetSeconds":0.24,"waCombinedOffsetsSeconds":{"sprint":0.24,"middle":0.14,"long":0}},"sources":[{"title":"Canonical HTTP binding at the documented implementation revision","url":"https://github.com/wickthumb/track_tools_pro_marketing/blob/b5a8aca7b85361476e0321a08b7fa5f516fc9535/lib/calculator-functions.ts","note":"Existing calculation handler; math metadata is additive."},{"title":"lib/formulas/fat-hand-time.ts","url":"https://github.com/wickthumb/track_tools_pro_marketing/blob/b5a8aca7b85361476e0321a08b7fa5f516fc9535/lib/formulas/fat-hand-time.ts","note":"Primary implementation source for these equations/tables, not a claim of scientific calibration."},{"title":"NFHS: Converting Times—Manual to FAT and English to Metric, 18 Dec 2014","url":"https://www.nfhs.org/resources/sports/converting-times-manual-to-fat-and-from-english-to-metric-distances","note":"Public NFHS conversion convention reference, not a claim that every governing body applies it."},{"title":"World Athletics / IAAF Combined Events Scoring Tables","url":"https://worldathletics.org/download/download?filename=53f7d332-be0c-434c-8467-1d9078966147.pdf&urlslug=IAAF+Scoring+Tables+for+Combined+Events","note":"1984 combined-event coefficient system; formula units and event-wise floor. Distinct from general 2025 athletics points."}]},"annotations":{"readOnlyHint":true,"consequentialHint":false},"name":"FAT vs Hand Time Converter","description":"Compare Fully Automatic Timing (FAT) and manual times using explicitly named NFHS seeding or World Athletics combined-event conventions. Forward conversion rounds manual times upward; reverse conversion is an estimate.","category":"Conversions & Adjustments","method":"POST","endpoint":"/api/calculators/fat-hand-time-converter","page":"/calculators/fat-hand-time-converter","inputSchema":{"type":"object","required":["timeSeconds","direction","eventCategory"],"properties":{"timeSeconds":{"type":"number","description":"Input time in seconds.","minimum":0},"direction":{"type":"string","description":"Convert hand time to FAT or FAT to hand.","enum":["handToFat","fatToHand"],"default":"handToFat"},"eventCategory":{"type":"string","description":"WA combined-event group: sprint below400m, middle400m, long above400m. NFHS uses0.24 for every group.","enum":["sprint","middle","long"],"default":"sprint"},"convention":{"type":"string","description":"Named conversion convention; reverse subtraction is an estimate, not recovered manual timing.","enum":["nfhs","waCombined"],"default":"nfhs"}}},"example":{"timeSeconds":10.8,"direction":"handToFat","eventCategory":"sprint"}}}