HowFast – Drag Race Predictor

Predict Your ET. Dial In. Win.

Free · In‑App Purchases

Real-time ET prediction, OBD-II gear detection, and run logging built for bracket racers. Free download — upgrade to Pro anytime. Know your number before you stage. HowFast predicts your elapsed time using your vehicle's real specs — engine, drivetrain, tires, and the air conditions at your track. Whether you're dialing in for bracket racing or just curious how quick your car really is, HowFast gives you a data-driven starting point that gets smarter every time you run. Predict with confidence HowFast builds your ET prediction from the ground up — horsepower, drivetrain loss, tire grip, shift times, and real-time density altitude correction. The more you run, the more accurate it gets. HowFast learns from your actual timeslips and adjusts future predictions automatically. Built for the track, not the spec sheet! No expensive GPS hardware required. Use your iPhone's built-in GPS for run detection and timing, or connect to a RaceBox or Qstarz external GPS unit for precision timing at up to 25Hz. HowFast automatically detects your run and starts logging — no tapping required. Your logbook, is always with you! Every run is saved with your predicted ET, actual ET, speed, and conditions. Review your history, spot trends, and see how your tune is progressing over the season. Export Every Run in the DynoLog app effortlessly! HowFast captures your ET, trap speed, 60-foot time, and atmospheric data at the strip. DynoLog is where that data becomes a permanent part of your build record — plotted on a performance timeline, correlated to every mod you've made, and exportable as a professional PDF build sheet. After your pass, tap Export to DynoLog or login and the run lands in your build log automatically — no manual entry, no duplicate imports, no data left behind. Upgrade to Pro — one time purchase, yours forever. Unlock the full HowFast experience with a single one-time purchase: OBD-II connectivity— see your RPM, TPS, gear you're in, in real time Multi-run comparison — overlay runs and telemetry to find where you're gaining or losing Unlimited vehicles in your garage CSV export — take your data anywhere HowFast Pro is a one-time purchase. No subscription, no recurring charges. Whether you're a seasoned bracket racer chasing a perfect dial or a weekend warrior seeing what your car can do, HowFast is the smartest co-driver you've never had.

Ratings & Reviews

  • 5.0
    out of 5
    3 Ratings

HowFast now has integration with the Dynolog app. This update allows you to share your runs three different ways — all live. Tap Export in HowFast for a one-tap deep link that brings the run straight into DynoLog. Export a full season as a .dynolog file for batch import. Or sign into your DynoLog account (using your Apple or Google ID) on both apps and enable cloud sync — runs arrive on your DynoLog timeline automatically in the background. You are not required to install/use Dynolog for HowFast to work. Dynolog is an excellent companion app to track your tunes/builds/mods/build investmen and performance.

Version 1.2

The developer, DtimesTwo Technologies LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Used to Track You

    The following data may be used to track you across apps and websites owned by other companies:

    • Location

  • Data Linked to You

    The following data may be collected and linked to your identity:

    • Location
    • User Content
    • Identifiers
    • Usage Data

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Accessibility

The developer has not yet indicated which accessibility features this app supports. Learn More

Information

Seller
DtimesTwo Technologies LLC
Size
15.4 MB
Category
Sports
Compatibility
Requires iOS 26.2 or later.
  • iPhone
    Requires iOS 26.2 or later.
  • iPad
    Requires iPadOS 26.2 or later.
Age Rating
13+
In-App Purchases
Yes
Copyright
© 2026 DtimesTwo Technologies, LLC
  • Developer Website
  • Privacy Policy

    • More by DtimesTwo Technologies LLC

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