About

An engine, not a lookup table

RateString is an independent California software company with one product: a permanent-disability rating engine for the state’s workers’-compensation system. WPI goes in; a DEU-style rating string, the combined PD, and the dollars come out — computed live, the way the Disability Evaluation Unit would compute them.

Why it exists

California rates permanent disability through a fixed pipeline — impairment number, WPI, the 1.4 adjustment, occupational variant, age, the Combined Values fold — defined by a 2005 schedule most practitioners still work through as a PDF and a dog-eared money chart. Every step is mechanical. All of it is checkable. So it should be software, and the software should show its work: not just the answer, but the string — the same notation raters, attorneys, and judges already read.

Verified against the State’s own math

Trust in a rating tool comes down to one question: does it match the schedule? RateString’s engine reproduces the DIR’s published worked examples end-to-end and ships behind an automated test suite that re-checks the tables on every build — the occupational-variant grid, the age table, the FEC ranks, the CVC, and the rate caps for every injury year since 2005. When we publish a figure in a guide, it is computed by the engine, not typed from memory.

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occupation titles mapped
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impairment listings
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years of rate tables
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automated engine tests

The methodology — sources, edge cases, and what the engine deliberately does not decide — is documented in full on the methodology page.

Who builds it

RateString is built and maintained by a practicing California workers’-compensation attorney — someone who reads DEU rating strings and settlement math for a living, and wanted the tool that should have existed already. The company speaks as RateString; the work stands on the verification, not a byline.

What it isn’t

RateString produces estimates for informational use. It is not legal advice, it does not decide apportionment or choose between competing medical opinions, and it is not a substitute for an official DEU rating. Rate the reports you have; the judgment calls stay yours. The fine print lives on the legal page.

Contact & elsewhere

Support, press, and everything else: [email protected]. Release notes land on the changelog.

@RateString on X ↗RateString on LinkedIn ↗
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