Julian Date to Modified Julian Date
Type a value in JD to get it in MJD instantly.
54875.5MJD
That moment falls on a Friday, day 44 of 2009 (UTC).
What it means
Where is that on the timeline?
All dates are UTC. Unix time and these counts ignore leap seconds; Excel serials follow the 1900 date system and start at 1 March 1900.
The math
How to convert JD to MJD
date = 1970-01-01 00:00:00 UTC + timestamp seconds. Excel serial = Unix ÷ 86,400 + 25,569; Julian Date = Unix ÷ 86,400 + 2,440,587.5.
Example: 2454876 JD = 54875.5 MJD.
Every unit
That moment in every format
Tables
JD to MJD conversion table
| JD | MJD |
|---|---|
| 2451545 JD | 51544.5 MJD |
| 2452162 JD | 52161.5 MJD |
| 2453319 JD | 53318.5 MJD |
| 2454476 JD | 54475.5 MJD |
| 2455634 JD | 55633.5 MJD |
| 2456791 JD | 56790.5 MJD |
| 2457949 JD | 57948.5 MJD |
| 2459106 JD | 59105.5 MJD |
| 2460263 JD | 60262.5 MJD |
| 2461421 JD | 61420.5 MJD |
| 2462578 JD | 62577.5 MJD |
| 2463736 JD | 63735.5 MJD |
| 2465443 JD | 65442.5 MJD |
MJD to JD conversion table
| MJD | JD |
|---|---|
| 51544 MJD | 2451544.5 JD |
| 52161 MJD | 2452161.5 JD |
| 53318 MJD | 2453318.5 JD |
| 54476 MJD | 2454476.5 JD |
| 55633 MJD | 2455633.5 JD |
| 56791 MJD | 2456791.5 JD |
| 57948 MJD | 2457948.5 JD |
| 59106 MJD | 2459106.5 JD |
| 60263 MJD | 2460263.5 JD |
| 61420 MJD | 2461420.5 JD |
| 62578 MJD | 2462578.5 JD |
| 63735 MJD | 2463735.5 JD |
| 65442 MJD | 2465442.5 JD |
Quick answers
Quick answers
- How many MJD is 1 JD?
- 1 JD is -2399999.5 MJD.
- How many MJD is 10 JD?
- 10 JD is -2399990.5 MJD.
- How many MJD is 2454876 JD?
- 2454876 JD is 54875.5 MJD.
The units
About these units
Julian Date (JD)
Days since noon on 1 January 4713 BC, used in astronomy.
Modified Julian Date (MJD)
Julian Date minus 2,400,000.5: days since 17 November 1858.
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