Onbello Legal is a free, public child support calculator built to meet the Judicial Council of California's Rule 5.275 certification standard — implementing Family Code § 4055 with 2026 federal and state tax tables, validated across 200+ test scenarios.
Example: $10,000 vs $4,000/mo · Single · 1 child · 20% timeshare
Every requirement in Rule 5.275 is a feature, not an afterthought.
Full statutory formula — K-factor table, timeshare multiplier, all TN brackets.
Deterministic mathFederal brackets, California income tax, SDI at 1.3% uncapped, SS wage base $184,500.
IRS Rev. Proc. 2025-32Flags Low-Income Adjustment eligibility at the $2,929/mo threshold with the required range on print output.
Rule 5.275 requiredOne-click print — LIA range on page 1, NMDI breakdown, input summary. Formatted for filing.
PDF readyChildcare and uninsured medical costs calculated separately with proportional allocation.
Senate Bill 343No account, no paywall, no profession gate. Open to attorneys, parties, mediators, and courts.
Open accessThe certified calculator market has contracted for years. DissoMaster is gone. The state's own calculator lost certification. Onbello Legal was built to fill the gap.
DissoMaster discontinued after decades as the dominant calculator.
DCSS public calculator certification revoked — failed to resubmit.
Onbello Legal submitted for certification — 200+ scenarios validated, 2026 tax tables, LIA detection, SB 343 add-ons.
Judicial Council review of live calculator at app.onbello.com/calculator.