This telescope magnification reference table shows the magnification for a range of telescope focal length values, assuming an eyepiece focal length of 25 mm. Every figure is computed with the same engine that powers our Telescope Magnification Calculator, so the numbers are exact.
| Telescope focal length | Magnification |
|---|---|
| 300 mm | 12.0 |
| 600 mm | 24.0 |
| 900 mm | 36.0 |
| 1,200 mm | 48.0 |
| 1,800 mm | 72.0 |
| 2,400 mm | 96.0 |
| 3,600 mm | 144.0 |
| 6,000 mm | 240.0 |
| 8,400 mm | 336.0 |
| 12,000 mm | 480.0 |
How to use this table
Find the row closest to your telescope focal length and read across to the magnification. For a value between two rows, the real figure sits between them — or enter your exact numbers in the Telescope Magnification Calculator for a precise answer.
Need a value that is not in the table? — the Telescope Magnification Calculator does it instantly, for free, with the formula and a worked example built in.
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