ESP 8266 Models


I know there are few models of the ESP 8266 wifi board. I just wondered if there is a guide on how to choose the appropriate ESP module for my project in general. nothing specific or I would have asked a different question.

I'm new to IoT and new to arduino so I'm trying to understand what should be enough for me and if I should look for another model because this one won't be enough for me.

Some sort of a table that gives you the differences between the models maybe?

Thank you in advance.

This might be a question better asked on as the chip is not a specific Arduino product but something that people have written an Arduino core for so code can be written and uploaded using the Arduino IDE.

I looked on that forum and found nothing. so it's probably non existent. I guess it's going to be a trial and error kind of think for me as I bet it was and will be for many others.

Thank you for pointing me to that site tho.

Here's some information on the different models: Most of them are really similar. Also there are different versions even of each module, for example there are ESP-01 with 512kB flash and others with 1MB flash. It's really hard to find specific information on them. The ESP-01 is very limited of IO pins and flash. It's confusing because some vendors use bits and some use bytes to describe the flash capacity(there are 8 bits in a byte), what's even worse they use the abbreviation M instead of the proper MB(megabyte) or Mb(megabit). Like it would kill them to add an extra letter to make things less confusing.

Most of the boards you will find use one of the ESP-12 module variants. My favorite is the WeMos D1 Mini. You can buy them for less than $3 USD on Aliexpress or $3.50 USD on eBay and they're nice and small. They have built in USB so you can plug them in and program them directly using the esp8266 Arduino core.

@pert Thank you for the suggestions. I already looked at the link you gave here but I understand I won't find anything like a table with all these variations.

About the WeMos module, how long do you have it and what is it's working distance? so I'll know fo rsure it's what I'm going to need.

Again thank you for your answer.

ALSO..... Does it have the voltage regulator for the 3.3V on it? or do I still need to have this thing set up?

I've been using the D1 Minis for around 6 months now. The only problems I've had is I got two of them that had something wrong with the USB and some of the Aliexpress shipments were really slow, like 6-7 weeks. That's out of around 25 I've bought.

I don't know about the range. I've only used them about 20 ft from my WiFi router. They just have a PCB antenna you definitely want to be careful about not blocking it with a metal enclosure or whatever. I'd guess you would get a better range with an external antenna. I have a couple of ESP8266 modules with the SMA connector for them but they're less common and I haven't seen a board with one. They also have modules with chip antenna available, there is a WeMos D1 Mini Pro that has one and more flash(though they haven't added that one to the ESP8266 Arduino core yet, maybe you can just use the regular D1 Mini board?). I'm not sure how much of a range improvement the chip antenna provides.

You should be aware of the difference between ESP8266 modules and boards. For example the D1 Mini uses one of the ESP-12 modules. The ESP8266 module is a circuit board with the ESP8266 chip, flash memory chip and the supporting passive components. Usually these components are under a metal shield. Usually there is an antenna also on the module. Other than the ESP-01, the modules have the contacts along the edge at a smaller than the normal 0.1 inch pitch and thus are not breadboard or prototyping board compatible. The boards such as the D1 Mini, NodeMCU, etc. add the USB circuitry and voltage regulator in addition to breaking the pins out at the standard 0.1 inch pitch. There are also boards like the WeMos D1 that have the Uno form factor so you can use the standard Arduino shields on them. The D1 Mini also has a variety of shields available.

You should be aware that the D1 Mini doesn't come with the header pins soldered on. This is actually a good thing because it allows you to decide which type of pins you want to use, male(to plug into breadboard or circuit board), female(for the shield), or male and female. They come with all 3 types of pins. It's very easy to solder them on with a little practice and this is something you'll need to learn eventually if you're going to get into working with electronics.

Yeah I figured out that I'll need to learn how to solder....

I'm not planning to have a metal enclosure on the parts but if I have concrete walls that may block my signal I just want to understand how strong is the signal? it's should be around the 30-40 ft but with concrete walls in between.

Thanks again for all the information it really helps me a lot!

They're pretty cheap so I'd suggest buying one to check it out. I've found the shipping from eBay to be much faster than Aliexpress for some reason even though they're both coming from China so if you want it sooner it might be worth spending the extra $0.75.

ok just to make sure....

I bought this one: WeMos D1

Do I need to make sure it gets the 3.3V? or does it have a voltage regulator on board?

Also can the USB port exceed the 3.3V and ruin the module?

Thanks a lot for all the suggestions and explanations.

There's a voltage regulator so you can power it with 5V via USB or the 5V pin. You can also power it directly with 3.3V via the 3.3V pin. The IO is 3.3V. There's some disagreement on whether the ESP8266 is 5V input tolerant on the IO pins, including a supposed statement from the CEO of the manufacturer saying it is. I've always shifted the input level to 3.3V to be safe but certainly many others have not without immediate problems.

There's some decent documentation at

I like the D1 Mini WeMos, but once you actually figure out what you're doing, and just have something simple like a sensor, a smaller module will be more efficient depending on your needs. The ESP-02 for example can take an external wifi antenna easily, if you need to enclose your project and move the antenna.