Handling API Limits and Error Responses

Handling API Limits and Error Responses



Hi Everyone,
Welcome back to yet another post in the Kaizen Series! 
We appreciate your keen participation in the 200th milestone celebration of the Kaizen series. We will continue to answer the queries we received through the feedback. 
When working with Zoho CRM APIs, you must respect API limits, handle errors properly, and deliver meaningful experiences—even when things go wrong. In this post, we will discuss handling API limits and error responses.

Understanding Zoho CRM API Limits

Zoho CRM enforces API limits based on the purchased user licenses and add-on credits, and this is to ensure availability to all users and prevent abuse of its APIs. The following limits are applicable to Zoho CRM REST APIs.

  • API Credits Limits: Each edition (Free, Standard, Professional, etc.) comes with a set number of API credits per rolling 24-hour window. For example, Enterprise/Zoho One offers a baseline of 50,000 plus 1,000 per user license, with a cap up to 5,000,000 credits including add-one credits. You can refer to our help documentation on API limits for more details.
  • Concurrency Limits: Concurrency is the number of parallel API calls that are active at one time instance. Apps are capped at concurrent requests based on CRM edition: Free (5), Standard (10), Professional (15), Enterprise (20), Ultimate (25).
  • Sub-Concurrency Limits: Some resource-intensive APIs have their own concurrency limits (typically 10 concurrent requests): bulk updates, queries, lead conversion, mail, etc. Exceeding these returns a TOO_MANY_REQUESTS error.
  • Limits per Call: Different APIs have specific limits for the number of resources that can be inserted/updated. For example for insert, update, or upsert records, you can pass up to 100 records in one API call. Refer to the individual help documentation for any such limits.

Tips:

  • Monitor Usage: Use Zoho’s dashboard to track API credits in real time. Set alerts if you are approaching limits. Alternatively, keep an eye on the header X-API-CREDITS-REMAINING which denotes the remaining credits that will be present in the response when your API usage exceeds 50 percent or the daily available credit limit. Also, you can customize your usage notification to receive an email alert.
  • Batch Operations: Prefer bulk inserts/updates (up to 100 records/call) to reduce wasteful requests. Use composite APIs when multiple APIs need to be executed. 
  • Space Out Calls: When integrating, use logical intervals and avoid call bursts to prevent concurrency /subconcurrency limit getting applied. We have covered this in more detail in our previous Kaizen post : How to effectively handle API calls to optimize API credits?

Limits in Zoho CRM GraphQL APIs

Like our REST APIs, our GraphQL API calls also consume credits based on the type and number of resources queried. Maximum allowed credits per call is 10 credits.
Complexity for each query is calculated based on the type and number of resources requested, and maximum allowed complexity is 1,000 per query. 
Depth refers to the number of nesting layers of a field. Depth up to seven for metadata and three for records is allowed.
You can refer to our GraphQL API documentation on Credits, Complexity, and Depth for more details.

Handling Errors

 Zoho CRM REST APIs return 200 status codes for every successful API call. Each API error has these sections:
  • Status Code 
  • Error Code 
  • Message 
Different sections of an error response
Here "resource_path_index": 0 in the response indicates which segment of the URL path contains the error, counting after the API version.

Common Errors

  • 400 Bad Request:  
    • INVALID_MODULE
      • Cause: Incorrect module name (e.g., "Lead" vs "Leads").
      • Fix: Use exact API names from Setup > Developer Space > APIs.
    • INVALID_DATA
      • Cause: Malformed JSON/wrong data type.
      • Fix: Validate field formats.
    • DUPLICATE_DATA
      • Cause: Unique field value exists elsewhere.
      • Fix: Disable "Do not allow duplicates" or change value.
    • MANDATORY_NOT_FOUND
      • Cause: Missing required field (e.g., Last_Name in Contacts while trying to insert a new record in Contacts module).
      • Fix: Include all mandatory fields in the request.
  •  401 Unauthorized: 
    • AUTHENTICATION_FAILED
      • Cause: Wrong domain URL .
      • Fix: Use the correct domain-specific URL.
    • INVALID_TOKEN:
      • Cause: Expired OAuth token is used for making API call.
      • Fix: Refresh access token using the refresh token.
  • 403 Forbidden: 
    • NO_PERMISSION
      • Cause: User lacks permission for the resource.
      • Fix: Obtain necessary permission to access the resource.
  •  404 Not Found: 
    • INVALID_URL_PATTERN
      • Cause: URL syntax error.
      • Fix: Verify endpoint structure in API docs.
  •  429 Too Many Requests: 
    • TOO_MANY_REQUESTS
      • Cause: Number of API requests for the 24 hour period is exceeded or the concurrency/sub-concurrency limit of the user for the app is exceeded.
      • Fix: Make calls in accordance with the limits.
  • 207 Multi-Status: 
    • In some cases when the API is partially successful, 207 status code is returned.

Tips

  • Mandatory Fields: Provide all mandatory fields in the response body.
  • OAuth Issues: Ensure correct scopes.
  • Inspect Every Response Body: Parse responses even if the HTTP status code returned is 2XX. 
  • Validate Data Before Calling: Ensure your request matches the expected format. Clean data before submission to prevent 400-range errors (e.g., MANDATORY_NOT_FOUND, DUPLICATE_DATA).
  • Token Issues: Respond to INVALID_TOKEN with a token refresh workflow.

Error Status Code in GraphQL APIs 

Zoho CRM GraphQL APIs return errors in 200 and 400 status codes depending on error type. 200 HTTP status codes are returned in two cases. 
(a) Issue in the input when validated against the schema .
(b) Runtime errors due to credits, depth, and so on.

Refer to the Status Codes and Responses page in GraphQL for more information.
We hope you found this post useful. We will be back next week to answer another query we received.
Let us know if you have any questions in the comments or drop us an email at support@zohocrm.com.

    • Sticky Posts

    • Kaizen #197: Frequently Asked Questions on GraphQL APIs

      🎊 Nearing 200th Kaizen Post – We want to hear from you! Do you have any questions, suggestions, or topics you would like us to cover in future posts? Your insights and suggestions help us shape future content and make this series better for everyone.
    • Kaizen #198: Using Client Script for Custom Validation in Blueprint

      Nearing 200th Kaizen Post – 1 More to the Big Two-Oh-Oh! Do you have any questions, suggestions, or topics you would like us to cover in future posts? Your insights and suggestions help us shape future content and make this series better for everyone.
    • Celebrating 200 posts of Kaizen! Share your ideas for the milestone post

      Hello Developers, We launched the Kaizen series in 2019 to share helpful content to support your Zoho CRM development journey. Staying true to its spirit—Kaizen Series: Continuous Improvement for Developer Experience—we've shared everything from FAQs
    • Kaizen #193: Creating different fields in Zoho CRM through API

      🎊 Nearing 200th Kaizen Post – We want to hear from you! Do you have any questions, suggestions, or topics you would like us to cover in future posts? Your insights and suggestions help us shape future content and make this series better for everyone.
    • Client Script | Update - Introducing Commands in Client Script!

      Have you ever wished you could trigger Client Script from contexts other than just the supported pages and events? Have you ever wanted to leverage the advantage of Client Script at your finger tip? Discover the power of Client Script - Commands! Commands

    Nederlandse Hulpbronnen


      • Recent Topics

      • How to add image to items list in Invoice or Estimate?

        Hello! I have just started using Zoho Invoice to create estimates and, possibly to switch from our current CRM/ERP Vendor to Zoho. I have a small company that is installing CCTV systems and Alarm systems. My question is, can I add images of my "items" to item list in Zoho Invoice and Estimates and their description? I would like to show my clients the image of items in our estimates so they can decide if they like these items. And I tell you, often they choose more expensive products just because
      • Zoho Calendar soft bounce on @hotmail.com and @yahoo.com email addresses

        Hello, our Zoho calendar recently does not send the calendar invites to emails with hotmail and yahoo domains and comes back with a "soft bounce". other domains like Gmail works fine. Also sending "email" to the same emails to the above domains work well
      • How can I filter a field integration?

        Hi,  I have a field integration from CRM "Products" in a form, and I have three product Categories in CRM. I only need to see Products of a category. Thanks for you answers.
      • ERROR CODE :512 - 5.4.4 DNS error:NXDOMAIN.

        Suddenly we cant send mail, we are getting this error for all outbound mail to multiple domains.
      • Can Zoho Flows repeat Actions more than once?

        I'm attempting to make an intentional Zoho Flow loop using the below layout. However, when "WithinLimit" condition is met, the program fails to execute the action "Get & Add Request Co..." again. Is this by design? Is Zoho Flows unable to repeat actions
      • Unveiling Cadences: Redefining CRM interactions with automated sequential follow-ups

        Last modified on 01/04/2024: Cadences is now available for all Zoho CRM users in all data centres (DCs). Note that it was previously an early access feature, available only upon request, and was also known as Cadences Studio. As of April 1, 2024, it's
      • customer data security

        We are exploring ways to enhance our within Zoho CRM. Our Goal: We want to fully integrate RingCentral with Zoho CRM to enable click-to-call functionality for our sales team. However, to comply with data privacy regulations and protect customer contact
      • Zoho Cliq not working on airplanes

        Hi, My team and I have been having this constant issue of cliq not working when connected to an airplane's wifi. Is there a reason for this? We have tried on different Airlines and it doesn't work on any of them. We need assistance here since we are constantly
      • Sync CRM inventory data with Zoho Books

        I just switched everything over to ZoHo books, but I am trying to find out why the CRM Estimates, Invoices, and Sales Orders created in ZoHo CRM are not then duplicated in ZoHo Books? I had Quickbooks before, and had to do everything twice, I thought
      • mask Customer phone number and agents cant see customer phone number

        Is there any way we can integrate Zoom Phone with Zoho CRM while ensuring that customer phone numbers remain masked? We need a solution where agents can make outbound calls but cannot see customer phone numbers. Please let us know if there is any solution
      • Email Reminders on Shared Calendars

        How do we turn off the setting that emails reminders to everyone who has accepted or declined a calendar invite? If 8 of us have been invited to the same meeting, we receive 8 notifications for every step of the process, from invitation to decision.
      • Default Sorting on Related Lists

        Is it possible to set the default sorting options on the related lists. For example on the Contact Details view I have related lists for activities, emails, products cases, notes etc... currently: Activities 'created date' newest first Emails - 'created
      • One Contact with Multiple Accounts with Portal enabled

        I have a contact that manages different accounts, so he needs to see the invoices of all the companies he manage in Portal but I found it not possible.. any idea? I tried to set different customers with the same email contact with the portal enabled and
      • WebDAV / FTP / SFTP protocols for syncing

        I believe the Zoho for Desktop app is built using a proprietary protocol. For the growing number of people using services such as odrive to sync multiple accounts from various providers (Google, Dropbox, Box, OneDrive, etc.) it would be really helpful if you implemented standard protocols such as WebDAV / FTP / SFTP so that alternative inc clients can be used.
      • What's New in Zoho Inventory | Q2 2025

        Hello Customers, The second quarter have been exciting months for Zoho Inventory! We’ve introduced impactful new features and enhancements to help you manage inventory operations with even greater precision and control. While we have many more exciting
      • How to refresh a ticket view ?

        I am doing a widget where I send a rest api call to make a new draft to the ticket I am viewing. The issue is sometimes it refresh a ticket view and I can see inserted draft right away, but sometimes I do not see it even if it is inserted correctly and
      • Ugh! - Text Box (Single Line) Not Enough - Text Box (Multi-line) Unavailable in PDF!

        I provide services, I do not sell items. In each estimate I send I provide a customized job description. A two or three sentence summary of the job to be performed. I need to be able to include this job description on each estimate I send as it's a critical
      • Merge Items

        Is there a work around for merging items? We currently have three names for one item, all have had a transaction associated so there is no deleting (just deactivating, which doesn't really help. It still appears so people are continuing to use it). I also can't assign inventory tracking to items used in past transactions, which I don't understand, this is an important feature moving forward.. It would be nice to merge into one item and be able to track inventory. Let me know if this is possible.
      • Supervisor Rules - Zoho Desk

        Hi, I have set up a Supervisor Rule in Zoho Desk to send an email alert when a ticket has been on hold for 48 hours. Is there a way to change it so that the alert only sends once and not on an hourly basis? Thank you Laura
      • ResponseCode 421, 4.7.0 [TSS04] Messages from 136.143.188.51 temporarily deferred due to user complaints

        Had email bounce. Let me know if you can fix this. Thanks. Michael
      • Zoho Canvas - Custom templates for related lists

        Hi, I see that the example pages load always one of our related lists in a custom template, but I dont know how to work with that:  1) How can i make my own custom templates for related lists?  2) Where and how can i check out existing custom templates?
      • Automation #15: Automatically Adding Static Secondary Contacts

        Rockel is a top-tier client of Zylker traders. Marcus handles communications with Rockel and would like to add Terence, the CTO of Zylker traders to the email conversations. In this case, the emails coming from user address rockel.com should have Terence
      • New Zoho triggers Google Dangerous flag due toabnormal charcters

        Just signed up and doing my first email test. I sent it to my google email account but it got flagged as Dangerous" due abnormal characters. My DNS setup looks ok. Page snips attached Help Please Thanks, Rick DC PowerWorld
      • Is there a API to fetch tasks in a Board/Section

        I am writing a scheduled function that retrieves all the tasks and send an reminder on cliq. I cannot seem to find a API to fetch tasks (by user / board / section) What are the way to fetch tasks?
      • Having trouble fetching contents of Zoho Connect Feeds using the API, requesting alternative API documentation.

        I'm trying to retrieve feed/post data from Zoho Connect using the API but facing challenges with the current documentation. What I've tried: OAuth authentication is working correctly (getting 200 OK responses) Tested multiple endpoints: /pulse/nativeapi/v2/feeds,
      • Adding an Account Name to Tasks/Reminders

        Does anyone know how to add the related account name to a task?  When we look at the list of activities and when the reminders pop up, there is no way of quickly seeing who the account is. 
      • Top Bar Shifting issue still not fixed yet

        I mentioned in a previous ticket that on Android, the top bar shifts up when you view collections or when you're in the settings. That issue still hasn't been fixed yet. I don't wanna have to reinstall the app as I've noticed for some reason, reinstalling
      • Triggering Zoho Flow on Workdrive File Label

        Right now Im trying to have a zoho flow trigger on the labeling/classification of a file in a folder. Looking at the trigger options they arent great for something like this. File event occurred is probably the most applicable, but the events it has arent
      • SendMail to multiple recipients

        Hi, I'm trying to send an email to a list of recipients.  Right now the "to" field is directed to a string variable. (List variables won't work here). In the string variable, how can I make it work? trying "user@app.com;user2@app.com" or "user@app.com; user2@app.com" just failed to send the emails. Ravid
      • Populate drop down field from another form's subform

        Hello, I found how to do that, but not in case of a subform. I have a Product form that has a subform for unit and prices. A product might have more than one unit. For example, the product "Brocoli" can be sold in unit at 3$ or in box of 10 at 25 $. Both
      • Usar o Inventory ou módulo customizado no CRM para Gestão de Estoque ?

        Minha maior dor hoje em usar o zoho é a gestão do meu estoque. Sou uma empresa de varejo e essa gestão é fundamental pra mim. Obviamente preciso que esse estoque seja visível no CRM, Inicialmente fiz através de módulos personalizados no próprio Zoho CRM,
      • Signup forms behaviour : Same email & multiple submissions

        My use case is that I have a signup form (FormA) that I use in several places on my website, with a hidden field so I can see where the contact has been made from. I also have a couple of other signup forms (FormB and FormC) that slight differences. All
      • getting error in project users api

        Hello, I'm getting a "Given URL is wrong" error when trying to use the Zoho Projects V3 API endpoint for adding users to a project. The URL I'm using is https://projectsapi.zoho.com/api/v3/portal/{portalid}/projects/{projectid}/projectusers/ and it's
      • Change total display format in weekly time logs

        Hi! Would it be possible to display the total of the value entered in the weekly time log in the same format that the user input? This could be an option in the general settings -> display daily timesheet total in XX.XX format or XX:XX.
      • Different Company Name for billing & shipping address

        We are using Zoho Books & Inventory for our Logistics and started to realize soon, that Zoho is not offering a dedicated field for a shipping address company name .. when we are creating carrier shipping labels, the Billing Address company name gets always
      • How to display historical ticket information of the total time spent in each status

        Hi All, Hoping someone can help me, as I am new to Zoho Analytics, and I am a little stuck. I am looking to create a bar chart that looks back over tickets raised in the previous month and displays how much time was spent in each status (With Customer,
      • Zoho Projects iOS app update: Global Web Tabs support

        Hello everyone! In the latest version(v3.10.10) of the Zoho Projects app update, we have brought in support for Global Web Tabs. You can now access the web tabs across all the projects from the Home module of the app. Please update the app to the latest
      • Zoho Community Weekend Maintenance: 13–15 Sep 2025

        Hi everyone, We wanted to give you a heads-up that Zoho Community will undergo scheduled maintenance this weekend. During this period, some community features will be temporarily unavailable, while others will be in read-only mode. Maintenance Window:
      • Agent Performance Report

        From data to decisions: A deep dive into ticketing system reports An agent performance report in a ticketing system provides a comprehensive view of how support agents manage customer tickets. It measures efficiency and quality by tracking key performance
      • Show both Vendor and Customers in contact statement

        Dear Sir, some companies like us working with companies as Vendor and Customers too !!! it mean we send invoice and also receive bill from them , so we need our all amount in one place , but in contact statement , is separate it as Vendor and Customer, 
      • Next Page