AG4 Battery Equivalent
AG4 is the LR626 cell: 1.5 V alkaline, 6.8 × 2.6 mm, so anything marked 177 and LR66 is the same battery and will fit.
Full LR626 page: every equivalent, the sizes and what not to use
- Chemistry
- alkaline
- Voltage
- 1.5 V
- Size (Ø × H)
- 6.8 × 2.6 mm
- Typical capacity
- 12–18 mAh
IEC designation LR626.
What the AG4 code is
AG4 is a generic trade number rather than an IEC designation. The AG series is common on generic and own-brand alkaline cells, sold in strips and multipacks, and it numbers the sizes in sequence instead of describing them.
The IEC code for the same cell is LR626, which is the number you will find on branded packs and in device manuals.
LR626 equivalents
Direct replacements
The same cell under another code. Any of these fits, whatever the brand.
- 177
- AG4
- LR66
Upgrade or downgrade
Same size, different chemistry. Read the verdict before you buy.
| Cell | Chemistry | Voltage | Verdict |
|---|---|---|---|
| SR626SW | silver oxide | 1.55 V | Upgrade Upgrade: steadier voltage, longer life. |
Similar size, check the fit
Same diameter, different thickness. These are not drop-in replacements.
| Cell | Size | Verdict |
|---|---|---|
| LR621 | 6.8 × 2.1 mm | Same 6.8 mm diameter, but 2.1 mm tall instead of 2.6 mm. Only if the holder fits; thinner cells can lose contact. |
AG4 questions
- What battery is AG4?
- AG4 is the LR626: a 1.5 V alkaline cell, 6.8 × 2.6 mm, with a typical capacity of 12–18 mAh.
- Is AG4 the same as LR626?
- Yes. They are two codes for one cell, so a pack marked either way holds the same battery.
- What can I use instead of AG4?
- Any code in the direct replacement list above. SR626SW is the same size in another chemistry: Upgrade: steadier voltage, longer life.
- What voltage is AG4?
- 1.5 V, the same as any other LR626.