Open data.
Aggregated refund timing, free to reuse with credit under CC BY 4.0.
Forecast endpoint
GET /api/forecast?season=2027&scenario=normal&anchor=ACC&week=6&path=0&cadence=unknown&day=10 returns the group's median and 10th and 90th percentile days, the share already paid and the number of timelines, or the IRS windows while the group is too small. Responses are cached for 10 minutes.
IRS weekly statistics
The IRS's weekly filing season statistics, collected every Friday from January to May, are in the refund schedule pages for each season.
What is never published
Individual timelines, device keys and anything about a single person. Aggregates are published only for groups of at least 8 timelines.