What is RSI? The Relative Strength Index in plain English
By SendPay Business · · 2 min read
- 1Type in your own numbers
- 2The tool works it out
- 3See the answer clearly
The Relative Strength Index (RSI) is a chart indicator, introduced by J. Welles Wilder in 1978, that measures how strongly a price has been rising compared with falling. It runs on a scale from 0 to 100.
How it is worked out
- Over the last 14 periods (the usual setting), find the average gain on up days and the average loss on down days.
- Divide the average gain by the average loss to get the relative strength (RS).
- RSI = 100 − 100 ÷ (1 + RS). Wilder smoothed the averages so each new period updates them gradually.
Reading the number
A reading above 70 is commonly called overbought and below 30 oversold, meaning the price has moved a long way in one direction recently. Around 50 means gains and losses have been roughly balanced.
Try it
Name your platform and watch it come to life
Type a name, tap a colour and pick what it does. The phone changes as you go.
Colour
What it does
Design and preview your whole platform free, then launch when you are ready.
The limits
In a strong trend RSI can stay above 70 or below 30 for a long time, so overbought doesn't mean a fall is due. It is built only from past prices and works best alongside other information.
Where SendPay fits
SendPay doesn't offer trading. SendPay platforms let your customers hold GBP, EUR and USD and exchange between them at a fee you set, alongside transfers and branded Visa cards, powered by licensed partners.
How it works
Your own money app- 1Name it and pick your colours
- 2Choose what it does
- 3Launch when you are ready
Why sign up
Create your free SendPay account
It's all about creating your own financial platform with ease. Start with a free account today.
- 🪪A free business accountOpen it in about a minute with your business name, email, password and mobile. No card and no documents to start.
- 💳Get paid from day oneTake card payments, and share your own payment link and invoices so customers pay in a click.
- 🌐A free business websiteFree to build, free to publish and free to keep, with unlimited visits.
- 🚀Your own financial platformDesign and preview your whole platform free, then launch when you are ready.
SendPay Business is a technology company, not a bank. Accounts, cards and payments are powered by licensed partners.
Questions people ask
Read next
Spotted a mistake or something out of date? and we'll fix it. How our guides are made
This guide is general information, not legal or financial advice. SendPay Business is a technology company, not a bank, and does not take deposits; regulated services on the platforms are provided by licensed partners. Other companies named in this guide are reference points only and are not affiliated with SendPay Business.