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Worked example
Real numbers from this tool, line by line.
If you learn Spanish with dual subtitles on Netflix or YouTube, the FSI number you need is 1,200 hours, not 690. At 30 minutes of watching plus 15 minutes of study, six days a week, that is 240 weeks.
Here is the whole calculation from the free calculator, with the default numbers:
- FSI weeks for Spanish: 30
- FSI class hours: 30 x 23 = 690
- FSI total, class plus self-study: 30 x (23 + 17) = 1,200
- Hours already studied: 120, so 1,080 are left
- Your week: (30 + 15) minutes x 6 days = 4.5 hours
- Weeks to the total: 1,080 / 4.5 = 240, about 4.6 years
Where the 1,200 comes from
The U.S. State Department's Foreign Service Institute publishes how long its students take to reach an ILR score of 3 in speaking and listening. The current page says: "A typical week is 23 hours per week in class and 17 hours of self-study." Spanish and French are listed at 30 weeks, Italian and Portuguese at 24, German at about 36, Russian and Polish at about 44, and Japanese, Korean, Chinese and Arabic at 88.
Most charts still quote 600 to 750 hours for Spanish. That is a class-hour figure. The page itself now lists 552 to 690 class hours for Category I, and those are only the hours in a classroom. Add the 17 self-study hours each week and Spanish becomes 1,200 hours. Japanese becomes 88 x 40 = 3,520.
One more detail: the page prints 2200 class hours for Category IV, but 88 x 23 = 2,024. The calculator uses weeks x 23 for every category, the same rule the page applies to the other three.
What your dual-subtitle minutes buy
FSI students put in 40 hours a week. The default example puts in 4.5. FSI's week is 8.9 times that. Nothing is wrong with a slow pace. The problem is not knowing it: a learner who expects to be done in a year at 45 minutes a day is planning on the wrong number.
Change one number and the answer moves:
- 60 minutes of subtitles instead of 30: 7.5 hours a week, 144 weeks to 1,200 hours
- Japanese at the same 60 minutes: 3,520 hours, 453 weeks
- To finish Spanish in one year from 120 hours done: 1,080 / 52 x 60 / 6 = 208 minutes per study day
The result is a best case. It counts every minute you spend like an FSI hour, and FSI hours are taught classes and directed self-study.
What the extension costs until then
If your subtitle extension costs $5.00 a month, 240 weeks is 240 / 52 x 12 = 55.4 months, or $276.92. Per study hour that is $5.00 x 12 / 234 = $0.26. Type your own plan price, or 0 if you use a free one.
Free and paid
The calculator in the browser is free and complete: 8 inputs, 12 results, as often as you like, nothing uploaded.
The paid Excel workbook adds what the browser cannot keep for you: a 104-week log from Monday 26 October 2026. Each Sunday you type the week's subtitle and study minutes. It shows hours done, hours left, whether you are ahead of plan, and the week you finish at your real pace. In the bundled test, a first week of 210 subtitle minutes and 90 study minutes gives 5 hours, 125 hours done and 0.5 hours ahead of plan. A fourth sheet lists all 59 languages on the FSI page with weeks, class hours and total hours.
Sources
U.S. Department of State, Foreign Service Institute, "Foreign Language Training" (state.gov/foreign-language-training, archived 13 January 2026, read 26 October 2026). Yardstick: BLS OEWS May 2025, self-enrichment education teachers (SOC 25-3021), median $22.50 an hour.
15 seconds — what it actually does
Questions people ask
What does the dual subtitles study hours calculator work out?
It takes the State Department's FSI weeks for your language, FSI's 23 class hours and 17 self-study hours per week, the hours you have already done and your daily dual-subtitle and study minutes. It returns FSI's total hours, the hours you still need, your weeks and years to that total, and what your extension plan costs until then.
Who is this calculator for?
English speakers who learn Spanish, French, German, Japanese or another language by watching Netflix or YouTube with dual subtitles in Firefox or Edge, usually after work. It is for anyone who pays a monthly plan for a subtitle extension and wants to know how many months of watching their goal really takes.
Why not just read the FSI chart that is already online?
Most charts copy the old 600 to 750 hours for Spanish and count class time only. The current FSI page lists 552 to 690 class hours for Category I and says a typical week is 23 class hours plus 17 hours of self-study. For Spanish that is 30 weeks x 40 hours = 1,200 hours. No chart divides that by your own minutes.
What is free and what is in the paid workbook?
The browser calculator is free and complete: 8 inputs and all 12 results, as often as you like, with nothing uploaded. The paid Excel workbook adds a 104-week log from Monday 26 October 2026 where you enter your real minutes each week and see hours left and your finish week, plus the FSI table of all 59 listed languages.
How does this compare with paying a tutor to plan my study?
The U.S. Bureau of Labor Statistics (OEWS, May 2025) puts the median pay of self-enrichment education teachers at $22.50 an hour. The calculator gives the same hour count in seconds from your own numbers. It does not replace lessons; it tells you how many hours your subtitle watching has to cover and at what pace.
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