
FlashCalc: Manual Flash Guide
Flash exposure assistant
0 ratings
Free
Rating summary
About
FlashCalc is a manual flash exposure assistant designed for photographers who shoot with on-camera and off-camera speedlights.
Whether you are balancing flash with ambient light or shooting entirely manual strobes, FlashCalc helps you dial in accurate exposures without guesswork.
KEY FEATURES:
• Dual Calculation Modes: Calculate required Flash Power ratio (1/1 to 1/128) based on your chosen aperture, or calculate recommended Aperture (f-stop) for a target power.
• Speedlight Zoom & GN Memory: Assign and save guide numbers across flash zoom positions (24mm to 105mm+).
• ISO Compensation: Automatically scales guide number outputs for different camera ISO values.
• EV Offset & Fraction Accuracy: View precise 1/3 and 1/10 stop EV offsets and calculated physical ratios.
• Rapid Distance Nudge: Quick stepper adjustments for subject distance in meters or feet.
• 100% Private & Offline: Works without internet or camera tethering. No tracking, accounts, or data collection.
Show more
+1
What's New in FlashCalc
1.0
October 23, 2026



