Now you know 50%, 80%, and 85% are important numbers in California sentencing. How much time an inmate will serve under these numbers varies depending on whether the sentence is served in county jail or state prison. If a sentence is served in county jail, how much time off for good behavior is given depends on the amount of overcrowding. Those who have passed through the Los Angeles County jail system are probably very familiar with 10%. That is how much of a jail sentence one will probably serve in Los Angeles County - 10%.
If I serve a 16 month state prison sentence and I have been in jail for 2 months now, lets answer "How Much Time I Have Left."
Here's how to calculate "How Much Time I Have Left."
1. Start with the number of actual credits already served in custody (beginning from the day arrested on the charge in the same county or from the date when transferred to the County where the charge occurred if in custody in a different county). In this case - 2 months.
2. Is the sentence a 50% or 80% sentence? If yes, then the amount of actual credits equals the amount of good conduct credits. In this case - 2 months.
3. Add the number of actual time credits to the number of good conduct credits. In this case - 2 months actual + 2 months good conduct credits = 4 months total credits.
4. Subtract the number of TOTAL credits from the prison sentence. In this case - 16 months minus 4 months total credits = 12 months remaining.
5. Reduce the REMAINING time to be served on the sentence based on whether it's a 50% or 80% sentence. In this case - If 50% is served, then 50% or 12 months remaining = 6 months LEFT. If 80% is served, then 12 months remaining X 80% = 9.6 months LEFT.
If I serve a 60 day county jail sentence and I have been in jail for 8 days now, "How Much Time I Have Left?" Answer: 22 days left.
Here's how I obtained that answer following the steps above.
1. 8 days actual credits (Number of actual credits already served)
2. 8 days good conduct credits (County Jail sentences are now reduced by 50%)
3. 8 days actual + 8 days good conduct = 16 days total credits (Add actual credits + good conduct credits)
4. 60 day sentence - 16 total credits = 44 days remaining
5. 44 days x 50% = 22 days left